refactor(mediabunny): [PKG-MB-04] isolate typed playback and readiness coordination

refactor/baselines/mb-coordination-validation.json

@@ -0,0 +1,728 @@
+{
+  "task": "PKG-MB-04",
+  "status": "done",
+  "parentCommit": "9af253a5a9db9c10062f7552f4e084582d5f6e94",
+  "sourceSha256LF": {
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+    "legacy": 72,
+    "artifactScope": "Each 72-case command includes 68 candidate assertions and four frozen normal-event controls."
+  },
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+      "native-mp4-playback-observed": 2,
+      "verified-unsupported-capability-control": 1
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+            "video:pause"
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+        "scope": "Identified proxy with native browser media and controlled ArtPlayer host using actual core utilities/config; frame timestamps sampled against the SDK audio clock, not acoustic/long-run AV-sync acceptance. Cleanup checks settled playback, not pending-operation races. Candidate trackless rejection is checked separately before decoder setup; this is not full release acceptance."
+      },
+      {
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+      },
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+      },
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+      },
+      {
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+      },
+      {
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+      },
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+      },
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+        "browser": "153.0.8010.12",
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+      },
+      {
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+        "scope": "Real browser ReadableStream and actual SDK Input disposal before first media bytes; real timeout; controlled ArtPlayer host; does not assert decoder, late frame or audio-node cleanup."
+      },
+      {
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+        "cancellations": [
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+        "scope": "Real browser ReadableStream and actual SDK Input disposal before first media bytes; real timeout; controlled ArtPlayer host; does not assert decoder, late frame or audio-node cleanup."
+      },
+      {
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+          "new"
+        ],
+        "scope": "Real browser ReadableStream and actual SDK Input disposal before first media bytes; real timeout; controlled ArtPlayer host; does not assert decoder, late frame or audio-node cleanup."
+      },
+      {
+        "project": "firefox",
+        "browser": "155.0",
+        "platform": "win32",
+        "implementation": "candidate-artifact",
+        "sha256": "01b88c915804e1c42b90c8c37aa948029472c7f47f6eb3a266629ed945be9fb1",
+        "ending": "timeout",
+        "outcome": "native-pending-stream-cancellation",
+        "cancellations": [
+          "old"
+        ],
+        "scope": "Real browser ReadableStream and actual SDK Input disposal before first media bytes; real timeout; controlled ArtPlayer host; does not assert decoder, late frame or audio-node cleanup."
+      },
+      {
+        "project": "webkit",
+        "browser": "26.6",
+        "platform": "win32",
+        "implementation": "candidate-artifact",
+        "sha256": "01b88c915804e1c42b90c8c37aa948029472c7f47f6eb3a266629ed945be9fb1",
+        "ending": "destroy",
+        "outcome": "native-pending-stream-cancellation",
+        "cancellations": [
+          "old"
+        ],
+        "scope": "Real browser ReadableStream and actual SDK Input disposal before first media bytes; real timeout; controlled ArtPlayer host; does not assert decoder, late frame or audio-node cleanup."
+      },
+      {
+        "project": "webkit",
+        "browser": "26.6",
+        "platform": "win32",
+        "implementation": "candidate-artifact",
+        "sha256": "01b88c915804e1c42b90c8c37aa948029472c7f47f6eb3a266629ed945be9fb1",
+        "ending": "source",
+        "outcome": "native-pending-stream-cancellation",
+        "cancellations": [
+          "old",
+          "new"
+        ],
+        "scope": "Real browser ReadableStream and actual SDK Input disposal before first media bytes; real timeout; controlled ArtPlayer host; does not assert decoder, late frame or audio-node cleanup."
+      },
+      {
+        "project": "webkit",
+        "browser": "26.6",
+        "platform": "win32",
+        "implementation": "candidate-artifact",
+        "sha256": "01b88c915804e1c42b90c8c37aa948029472c7f47f6eb3a266629ed945be9fb1",
+        "ending": "timeout",
+        "outcome": "native-pending-stream-cancellation",
+        "cancellations": [
+          "old"
+        ],
+        "scope": "Real browser ReadableStream and actual SDK Input disposal before first media bytes; real timeout; controlled ArtPlayer host; does not assert decoder, late frame or audio-node cleanup."
+      },
+      {
+        "project": "chromium",
+        "browser": "153.0.8010.12",
+        "platform": "win32",
+        "implementation": "candidate-artifact",
+        "sha256": "01b88c915804e1c42b90c8c37aa948029472c7f47f6eb3a266629ed945be9fb1",
+        "scenario": "callback",
+        "outcome": "native-synthetic-raf",
+        "result": {
+          "idType": "number",
+          "calls": [
+            {
+              "owner": "first",
+              "time": "number",
+              "mediaTime": 0,
+              "presentedFrames": 0
+            }
+          ],
+          "listeners": 0
+        },
+        "scope": "Real browser requestAnimationFrame and actual proxy instances; synthetic metadata is preserved, no decoding or video frame accuracy is claimed."
+      },
+      {
+        "project": "chromium",
+        "browser": "153.0.8010.12",
+        "platform": "win32",
+        "implementation": "candidate-artifact",
+        "sha256": "01b88c915804e1c42b90c8c37aa948029472c7f47f6eb3a266629ed945be9fb1",
+        "scenario": "destroy",
+        "outcome": "native-synthetic-raf",
+        "result": {
+          "idType": "number",
+          "calls": [],
+          "listeners": 0
+        },
+        "scope": "Real browser requestAnimationFrame and actual proxy instances; synthetic metadata is preserved, no decoding or video frame accuracy is claimed."
+      },
+      {
+        "project": "chromium",
+        "browser": "153.0.8010.12",
+        "platform": "win32",
+        "implementation": "candidate-artifact",
+        "sha256": "01b88c915804e1c42b90c8c37aa948029472c7f47f6eb3a266629ed945be9fb1",
+        "scenario": "independent",
+        "outcome": "native-synthetic-raf",
+        "result": {
+          "idType": "number",
+          "calls": [
+            {
+              "owner": "second"
+            }
+          ],
+          "listeners": 0
+        },
+        "scope": "Real browser requestAnimationFrame and actual proxy instances; synthetic metadata is preserved, no decoding or video frame accuracy is claimed."
+      },
+      {
+        "project": "firefox",
+        "browser": "155.0",
+        "platform": "win32",
+        "implementation": "candidate-artifact",
+        "sha256": "01b88c915804e1c42b90c8c37aa948029472c7f47f6eb3a266629ed945be9fb1",
+        "scenario": "callback",
+        "outcome": "native-synthetic-raf",
+        "result": {
+          "idType": "number",
+          "calls": [
+            {
+              "owner": "first",
+              "time": "number",
+              "mediaTime": 0,
+              "presentedFrames": 0
+            }
+          ],
+          "listeners": 0
+        },
+        "scope": "Real browser requestAnimationFrame and actual proxy instances; synthetic metadata is preserved, no decoding or video frame accuracy is claimed."
+      },
+      {
+        "project": "firefox",
+        "browser": "155.0",
+        "platform": "win32",
+        "implementation": "candidate-artifact",
+        "sha256": "01b88c915804e1c42b90c8c37aa948029472c7f47f6eb3a266629ed945be9fb1",
+        "scenario": "destroy",
+        "outcome": "native-synthetic-raf",
+        "result": {
+          "idType": "number",
+          "calls": [],
+          "listeners": 0
+        },
+        "scope": "Real browser requestAnimationFrame and actual proxy instances; synthetic metadata is preserved, no decoding or video frame accuracy is claimed."
+      },
+      {
+        "project": "firefox",
+        "browser": "155.0",
+        "platform": "win32",
+        "implementation": "candidate-artifact",
+        "sha256": "01b88c915804e1c42b90c8c37aa948029472c7f47f6eb3a266629ed945be9fb1",
+        "scenario": "independent",
+        "outcome": "native-synthetic-raf",
+        "result": {
+          "idType": "number",
+          "calls": [
+            {
+              "owner": "second"
+            }
+          ],
+          "listeners": 0
+        },
+        "scope": "Real browser requestAnimationFrame and actual proxy instances; synthetic metadata is preserved, no decoding or video frame accuracy is claimed."
+      },
+      {
+        "project": "webkit",
+        "browser": "26.6",
+        "platform": "win32",
+        "implementation": "candidate-artifact",
+        "sha256": "01b88c915804e1c42b90c8c37aa948029472c7f47f6eb3a266629ed945be9fb1",
+        "scenario": "callback",
+        "outcome": "native-synthetic-raf",
+        "result": {
+          "idType": "number",
+          "calls": [
+            {
+              "owner": "first",
+              "time": "number",
+              "mediaTime": 0,
+              "presentedFrames": 0
+            }
+          ],
+          "listeners": 0
+        },
+        "scope": "Real browser requestAnimationFrame and actual proxy instances; synthetic metadata is preserved, no decoding or video frame accuracy is claimed."
+      },
+      {
+        "project": "webkit",
+        "browser": "26.6",
+        "platform": "win32",
+        "implementation": "candidate-artifact",
+        "sha256": "01b88c915804e1c42b90c8c37aa948029472c7f47f6eb3a266629ed945be9fb1",
+        "scenario": "destroy",
+        "outcome": "native-synthetic-raf",
+        "result": {
+          "idType": "number",
+          "calls": [],
+          "listeners": 0
+        },
+        "scope": "Real browser requestAnimationFrame and actual proxy instances; synthetic metadata is preserved, no decoding or video frame accuracy is claimed."
+      },
+      {
+        "project": "webkit",
+        "browser": "26.6",
+        "platform": "win32",
+        "implementation": "candidate-artifact",
+        "sha256": "01b88c915804e1c42b90c8c37aa948029472c7f47f6eb3a266629ed945be9fb1",
+        "scenario": "independent",
+        "outcome": "native-synthetic-raf",
+        "result": {
+          "idType": "number",
+          "calls": [
+            {
+              "owner": "second"
+            }
+          ],
+          "listeners": 0
+        },
+        "scope": "Real browser requestAnimationFrame and actual proxy instances; synthetic metadata is preserved, no decoding or video frame accuracy is claimed."
+      },
+      {
+        "project": "chromium",
+        "browser": "153.0.8010.12",
+        "platform": "win32",
+        "implementation": "candidate-artifact",
+        "sha256": "01b88c915804e1c42b90c8c37aa948029472c7f47f6eb3a266629ed945be9fb1",
+        "outcome": "native-mp4-playback-observed",
+        "scope": "Identified published or candidate proxy with actual core5.4.0; native MP4 pixels/clock or explicitly unsupported Windows WebKit APIs. No HLS or long-run AV-sync acceptance."
+      },
+      {
+        "project": "firefox",
+        "browser": "155.0",
+        "platform": "win32",
+        "implementation": "candidate-artifact",
+        "sha256": "01b88c915804e1c42b90c8c37aa948029472c7f47f6eb3a266629ed945be9fb1",
+        "outcome": "native-mp4-playback-observed",
+        "scope": "Identified published or candidate proxy with actual core5.4.0; native MP4 pixels/clock or explicitly unsupported Windows WebKit APIs. No HLS or long-run AV-sync acceptance."
+      },
+      {
+        "project": "webkit",
+        "browser": "26.6",
+        "platform": "win32",
+        "implementation": "candidate-artifact",
+        "sha256": "01b88c915804e1c42b90c8c37aa948029472c7f47f6eb3a266629ed945be9fb1",
+        "outcome": "verified-unsupported-capability-control",
+        "scope": "Identified published or candidate proxy with actual core5.4.0; native MP4 pixels/clock or explicitly unsupported Windows WebKit APIs. No HLS or long-run AV-sync acceptance."
+      }
+    ],
+    "report": "refactor/.cache/mb04-coordination-results/report.json",
+    "reportSha256": "17dbd77680e414f0b27e94e278b24d46cd6cde443ed1bb96dcc2f3d285a6557f",
+    "results": "refactor/.cache/mb04-coordination-results/results"
+  },
+  "checks": [
+    {
+      "command": "yarn test:mediabunny",
+      "result": "pass",
+      "tests": 108
+    },
+    {
+      "command": "main/legacy shim, load and coordinator tests",
+      "result": "pass",
+      "eachRun": 72
+    },
+    {
+      "command": "same 40 coordinator assertions on adba8a3d main",
+      "result": "expected historical failures",
+      "passed": 8,
+      "failed": 32
+    },
+    {
+      "command": "package strict tsc and focused eslint --no-fix",
+      "result": "pass",
+      "productionModules": 16,
+      "temporaryDecoderDeclarationBridges": 2
+    },
+    {
+      "command": "yarn build artplayer-proxy-mediabunny",
+      "result": "pass",
+      "formats": [
+        "main",
+        "legacy",
+        "esm"
+      ]
+    },
+    {
+      "command": "four browser specs with built main",
+      "result": "pass",
+      "tests": 39
+    },
+    {
+      "command": "yarn ci:check",
+      "result": "pass",
+      "tests": {
+        "unit": 1114,
+        "engineering": 14,
+        "baseline": 141,
+        "mainTotal": 1269,
+        "repeatedContractExecutions": 44
+      },
+      "strictProductionTypeScriptFiles": 306,
+      "log": "refactor/.cache/mb04-coordination-ci.log"
+    },
+    {
+      "command": "built ESM default export and source function name",
+      "result": "pass",
+      "log": "refactor/.cache/mb04-coordination-esm.log"
+    }
+  ],
+  "limitations": [
+    "AudioEngine and VideoEngine remain JS behind explicit temporary declarations; their late internal work is MB-05/06.",
+    "Six Windows WebKit capability controls are not successful playback.",
+    "Trackless false readiness is corrected; existing-track unsupported codec behavior remains a capability/decoder task.",
+    "Synthetic RAF is not decoded frame accuracy; native sampled frames and short clocks are not long-run AV sync.",
+    "HLS query source ownership is guarded; full concurrent selection/UI topology remains MB-07.",
+    "No npm release or next-major approval is implied."
+  ]
+}

refactor/changes/2026-09-12-PKG-MB-04-coordination.md

@@ -0,0 +1,56 @@
+# PKG-MB-04：VideoShim、事件与主协调器
+
+任务通过完整CI后标记done，并立即以专用本地提交交付。前置shim检查点为9af253a5；本轮将
+MediaBunnyEngine.js实际迁移为严格TS，删除其临时声明桥。包内现在16个生产TS模块，
+AudioEngine/VideoEngine两个显式临时声明桥不计作实现迁移，分别留给MB-06/05。
+文件职责、状态归属、错误传播和继续维护入口见包内ARCHITECTURE.md。
+
+## 行为修复与兼容性
+
+- playback.ts独立管理播放意图和操作完成信号；pause能够阻止pending play或seek恢复，
+  新操作使旧结果失效。取消可先结束公开Promise，底层晚结果仍被观察。
+- seek完成信号先于可选恢复播放，避免play等待seek而seek又等待play的死锁。
+  play-pause-play共享尚未结束的audio resume，只有当前操作启动video和发送play/playing。
+- 每次就绪/播放事件前重新检查归属，允许用户在回调中同步切源、销毁或改变播放状态。
+  正常play/pause、seek/resume和HLS replacement事件顺序由对照测试保持。
+- 两个metadata参与者均完成才发布一次metadata；无轨道容器提前报code 4，信息为
+  `Input has no audio or video tracks.`，不再错误地readyState 4。有效媒体行为保持。
+- 活动play失败保留原始Promise拒绝并恢复paused；活动seek失败报告一次error并拒绝。
+  currentTime同步setter观察无法返回的拒绝，直接调用engine.seek仍能捕获错误。
+- HLS旧source查询失败不污染新source，当前查询失败继续拒绝；replacement改变media对象
+  后的活动错误也不能被误认为旧查询并吞掉。
+- destroy尽力执行所有input/audio/video释放步骤，之后保留首个异常；shim仍以finally
+  清理事件和synthetic RAF。事件安静不等于底层解码器晚操作已完全停止。
+
+工厂签名、公开声明、canvas描述符和同步/Promise接口保持。正常事件顺序、方法转发及
+描述符对照继续纳入验证。非正常行为差异是以上明确的竞态/错误修复，不宣称逐字节行为不变。
+旧createTimeout帮助方法保持原样，受管理的load路径不使用它；不要称所有手动调用的内部
+帮助方法也都具备自动取消。
+
+## 验证
+
+新增40项协调器测试，使用实际构建代理、受控异步音视频操作和实际SDK解析输入。
+同一断言对adba8a3d冻结main为8通过/32失败，候选全部通过。包专项108项通过。
+main与legacy各72项通过，其中68候选产物断言、4冻结正常事件对照。三格式构建通过。
+
+初轮main产物测试有一条断言把新source合法waiting/loadstart误当作旧replacement事件。
+已缩小到旧seek/readiness结果并保留完整禁止列表，重新运行main/legacy均72通过；未修改
+生产代码来消除新来源合法事件。历史同断言仍32失败，修复回归证据没有被放宽掉。
+
+浏览器报告及整个results归档后记录到mb-coordination-validation.json。39项候选检查区分
+12真实播放、9原生Stream取消、9synthetic RAF、6Windows WebKit能力对照及3无轨道拒绝。
+WebM在Chromium/Firefox另验证真实播放的play回调内pause后不会再发playing。
+此断言附属于现有播放用例，不增加测试数量。长播放、听觉输出和AV同步仍为MB-09。
+
+## 后续边界
+
+MB-05/06继续实际视频帧、解码器迭代器和Web Audio调度迁移；两处声明桥必须移除。
+MB-07继续HLS控件拓扑与并发选轨；MB-08完整公开类型/工厂兼容矩阵；MB-09/10完成组合、
+长播放、demo、真实安装包与许可通知。MB-LIFE-01/MB-READY-01保持open并更新已修复范围，
+既有轨道但不支持codec的路径仍需要解码器验证。此任务不构成npm发布验收。
+
+最终完整CI1269项（1114单元+14工程+141基线）通过，另44重复契约；306生产TS。
+所有记录的源码/测试/产物及报告哈希已核验，三格式docs/compiled与dist一致。ESM默认工厂
+及实际源码名称artplayerProxyMediabunny保持；首次临时检查误写大小写，已按实际入口修正。
+回退本任务可revert专用提交；旧shim检查点9af253a5与更早adba8a3d基线仍可对照。
+未推送、打tag或发布；下一项PKG-MB-05处理视频迭代器、晚帧与seek释放。

refactor/mb-validation.md

@@ -45,3 +45,12 @@ MB-03实施将input分离为六个strict TS模块，接入加载session、Range
 Chrome连接不可用时可使用内置浏览器；CLI自动化也按现有Playwright三引擎流程执行。
 保留report.json及整个results目录。受控输入不能替代真实解码，iframe不能替代原生Document PiP。
 VAST脚本VPN豁免不适用于本包。
+
+## MB-04 coordinator implementation
+
+VideoShim/EventTarget与主协调器已拆为严格TS模块，详情见
+[协调器变更](changes/2026-09-12-PKG-MB-04-coordination.md)及
+[验证记录](baselines/mb-coordination-validation.json)。包专项命令已包含新的协调器回归用例。
+无轨道容器由历史readyState 4改为code 4错误；有效媒体的正常顺序保持，重复就绪和
+失效操作结果被阻止。不要把synthetic RAF、受控竞态或Windows WebKit能力对照计为真实播放。
+音视频解码器仍通过两个显式声明桥连接，MB-05/06继续实际实现迁移和底层晚操作清理。

refactor/plan.md

@@ -4,7 +4,7 @@
 
 基线：`40fcda6a37d0049d42e49c1e64e70d4fd9ba5f7f`。总任务 222 项，范围 22 个包及工作区/示例。
 
-状态：todo 114 / doing 8 / blocked 0 / done 100 / deferred 0。风险 L/M/H 表示兼容风险，不表示工期。
+状态：todo 114 / doing 7 / blocked 0 / done 101 / deferred 0。风险 L/M/H 表示兼容风险，不表示工期。
 
 前置依赖是启动条件；验收是完成条件。任务可以继续拆分，但不能复用或悄悄删除旧 ID。
 
@@ -332,7 +332,7 @@
 | PKG-MB-01 | artplayer-proxy-mediabunny<br>核对 shim 与媒体契约 | BASE-05 | 全部 option、art.mediabunny、canvas/shim 属性及事件表 | 公开暴露成员和实际发布依赖/资源范围明确；核实 third-party.json 所记录依赖 MPL-2.0 元数据与实际 bundle 的许可/通知范围，不从根 MIT 推断 | H | done |
 | PKG-MB-02 | artplayer-proxy-mediabunny<br>建立真实媒体与事件基线 | PKG-MB-01, ENG-05, ENG-08 | MP4/WebM/HLS/Blob/Stream、seek/错误/轨道切换样本 | ready 事件顺序、音画同步、超时和释放可重跑 | H | done |
 | PKG-MB-03 | artplayer-proxy-mediabunny<br>整理 input 与加载取消 | PKG-MB-02, CORE-09 | input.js 源检测、输入资源、Range 与取消 | HLS 检测在 input 边界，旧来源类型和超时保持 | H | done |
-| PKG-MB-04 | artplayer-proxy-mediabunny<br>整理 VideoShim/EventTarget/Engine 协调 | PKG-MB-03, CORE-06, CORE-11 | shim 描述符、事件桥、加载状态和操作隔离 | 公开属性/同步异步返回与事件重入顺序保持 | H | doing |
+| PKG-MB-04 | artplayer-proxy-mediabunny<br>整理 VideoShim/EventTarget/Engine 协调 | PKG-MB-03, CORE-06, CORE-11 | shim 描述符、事件桥、加载状态和操作隔离 | 公开属性/同步异步返回与事件重入顺序保持 | H | done |
 | PKG-MB-05 | artplayer-proxy-mediabunny<br>整理视频解码、seek 和帧释放 | PKG-MB-04 | VideoEngine 调度、队列、晚帧处理和资源释放 | 暂停/seek/切源无旧帧覆盖，默认丢帧策略不变 | H | todo |
 | PKG-MB-06 | artplayer-proxy-mediabunny<br>整理音频解码、时钟与同步 | PKG-MB-04 | AudioEngine 时钟、缓冲和 AudioContext 归属 | AV sync、倍速、无音轨、静音/音量和暂停恢复通过 | H | todo |
 | PKG-MB-07 | artplayer-proxy-mediabunny<br>整理 HLS 配对轨道与 selector | PKG-MB-05, PKG-MB-06, CORE-14 | m3u8 配对、质量/音频选择及拓扑清理 | 实际选择高亮、切到无轨道来源清理、无重复 readiness | H | todo |
@@ -523,5 +523,5 @@
 - PKG-MB-01: [记录](baselines/mb-release.json) [记录](baselines/mb-surface.json) [记录](baselines/mb-contract.md) [记录](baselines/mb-contract-validation.json) [记录](mb-validation.md) [记录](changes/2026-09-12-PKG-MB-01-contract.md)
 - PKG-MB-02: [记录](changes/2026-09-12-PKG-MB-02-checkpoint.md) [记录](baselines/mb-media-checkpoint.json) [记录](mb-validation.md) [记录](changes/2026-09-12-PKG-MB-02-baseline.md) [记录](baselines/mb-behavior-validation.json)
 - PKG-MB-03: [记录](changes/2026-09-12-PKG-MB-03-input.md) [记录](baselines/mb-input-validation.json)
-- PKG-MB-04: [记录](baselines/mb-coordination-source.json) [记录](changes/2026-09-12-PKG-MB-04-shim-checkpoint.md) [记录](baselines/mb-shim-checkpoint.json)
+- PKG-MB-04: [记录](baselines/mb-coordination-source.json) [记录](changes/2026-09-12-PKG-MB-04-shim-checkpoint.md) [记录](baselines/mb-shim-checkpoint.json) [记录](changes/2026-09-12-PKG-MB-04-coordination.md) [记录](baselines/mb-coordination-validation.json)
 - PKG-FACTORY-01: [记录](baselines/factory-assignment-gaps.json) [记录](baselines/factory-compatibility-proposals.json) [记录](factory-compatibility-decision.md) [记录](changes/2026-09-12-PKG-FACTORY-01-decision.md)

refactor/progress.md

@@ -1,5 +1,17 @@
 # 进度与证据
 
+## PKG-MB-04完成：主协调器TS与操作隔离
+
+MediaBunnyEngine实际迁移TS，并拆分playback/readiness/HLS查询职责；正常接口和事件顺序
+保持，修复旧play/seek覆盖、错误吞掉、重复就绪及无轨道假就绪。新增40项测试在旧main上
+8通过/32失败，候选全通过；包专项108通过、main/legacy各72通过。最终39项浏览器
+包括12真实播放、9Stream取消、9synthetic RAF、6能力对照及3无轨道拒绝；另在已有
+Chromium/Firefox播放用例内验证play回调同步pause后无playing。完整CI1269通过，
+另44重复契约，306生产TS；包内16生产TS和2个未迁移解码器声明桥明确区分。
+见[变更](changes/2026-09-12-PKG-MB-04-coordination.md)及[证据](baselines/mb-coordination-validation.json)。
+222项：101 done、7 doing、114 todo；立即专用本地提交，下一项MB-05视频帧资源。
+MB-LIFE-01/MB-READY-01剩余解码器/能力与组合范围仍open；不构成npm发布验收。
+
 ## 当前检查点：PKG-MB-04 VideoShim、事件与RAF资源
 
 新增五个生产TS模块，保持shim/canvas布局和正常事件/Promise/属性契约；修复销毁后的RAF、

refactor/risks.json

@@ -3648,7 +3648,7 @@
         "PKG-MB-07",
         "PKG-MB-09"
       ],
-      "compatibleResolution": "Reproduce pending operations and destroy/source-switch races before migrating each owner; preserve public event and promise behavior while preventing stale resource use. MB-02 now reproduces late load rejection and uncancelled waiting/loadstart timers after destroy in all three historical implementations using a controlled host. Other interleavings and full-core native behavior are not yet verified. Expanded MB-02 baseline reproduces play-after-pause/destroy, rejected-play false state, seek-after-destroy and retained successful-load timeout timers in all three actual historical implementations; Range and active-timeout normal controls remain separate. MB-03 candidate owns pending Input before track selection and cancels load/HEAD/timers on source replacement, timeout and destroy; source/main/legacy regressions pass. Pending play/seek, late decoder work and full readiness coordination remain MB-04/05/06, so this risk stays open. MB-04 shim checkpoint fixes synthetic RAF retention and terminal event-listener cleanup, including engine cleanup exceptions. Closing the event bridge does not prove pending engine operations stopped; coordination remains in progress.",
+      "compatibleResolution": "Reproduce pending operations and destroy/source-switch races before migrating each owner; preserve public event and promise behavior while preventing stale resource use. MB-02 now reproduces late load rejection and uncancelled waiting/loadstart timers after destroy in all three historical implementations using a controlled host. Other interleavings and full-core native behavior are not yet verified. Expanded MB-02 baseline reproduces play-after-pause/destroy, rejected-play false state, seek-after-destroy and retained successful-load timeout timers in all three actual historical implementations; Range and active-timeout normal controls remain separate. MB-03 candidate owns pending Input before track selection and cancels load/HEAD/timers on source replacement, timeout and destroy; source/main/legacy regressions pass. Pending play/seek, late decoder work and full readiness coordination remain MB-04/05/06, so this risk stays open. MB-04 shim checkpoint fixes synthetic RAF retention and terminal event-listener cleanup, including engine cleanup exceptions. Closing the event bridge does not prove pending engine operations stopped; coordination remains in progress. MB-04 now guards play/seek/replacement completion, preserves explicit pause, observes stale failures and isolates reentrant event sequences. Decoder-internal late frames/audio and HLS UI races remain MB-05/06/07; risk stays open.",
       "closureCriteria": "Historical failing interleavings and candidate cancellation/cleanup pass with real media and event evidence, including long playback and track topology.",
       "status": "open",
       "evidence": [
@@ -3660,7 +3660,9 @@
         "refactor/changes/2026-09-12-PKG-MB-02-baseline.md",
         "refactor/baselines/mb-behavior-validation.json",
         "refactor/changes/2026-09-12-PKG-MB-03-input.md",
-        "refactor/changes/2026-09-12-PKG-MB-04-shim-checkpoint.md"
+        "refactor/changes/2026-09-12-PKG-MB-04-shim-checkpoint.md",
+        "refactor/changes/2026-09-12-PKG-MB-04-coordination.md",
+        "refactor/baselines/mb-coordination-validation.json"
       ]
     },
     {
@@ -3707,11 +3709,13 @@
         "PKG-MB-04",
         "PKG-MB-09"
       ],
-      "compatibleResolution": "Use explicit coordinated readiness and failure state, preserving valid event order while preventing duplicate or stale callbacks; evaluate trackless behavior separately from normal media.",
+      "compatibleResolution": "Use explicit coordinated readiness and failure state, preserving valid event order while preventing duplicate or stale callbacks; evaluate trackless behavior separately from normal media. MB-04 coordinates metadata once, suppresses stale readiness and rejects trackless input before decoder setup. Existing-track unsupported-codec behavior and full native combinations remain MB-05/06/09; risk stays open.",
       "closureCriteria": "Candidate metadata/data/canplay ordering and counts pass normal, absent-track and failure interleavings in native browsers and controlled race tests.",
       "evidence": [
         "refactor/changes/2026-09-12-PKG-MB-02-baseline.md",
-        "refactor/baselines/mb-behavior-validation.json"
+        "refactor/baselines/mb-behavior-validation.json",
+        "refactor/changes/2026-09-12-PKG-MB-04-coordination.md",
+        "refactor/baselines/mb-coordination-validation.json"
       ]
     }
   ]

refactor/tasks.json

@@ -3460,14 +3460,16 @@
         "CORE-06",
         "CORE-11"
       ],
-      "status": "doing",
+      "status": "done",
       "risk": "H",
       "deliverable": "shim 描述符、事件桥、加载状态和操作隔离",
       "acceptance": "公开属性/同步异步返回与事件重入顺序保持",
       "evidence": [
         "baselines/mb-coordination-source.json",
         "changes/2026-09-12-PKG-MB-04-shim-checkpoint.md",
-        "baselines/mb-shim-checkpoint.json"
+        "baselines/mb-shim-checkpoint.json",
+        "changes/2026-09-12-PKG-MB-04-coordination.md",
+        "baselines/mb-coordination-validation.json"
       ]
     },
     {