feat(html-player): add feature-flagged shared controls (#1194)

* feat(html-player): bridge engine state to shared controls

* fix(html-player): avoid HLS subtitle event reentry

* fix(html-player): restore delayed HLS default subtitles

* refactor(html-player): split controls bridge collaborators

* feat(html-player): add feature-flagged shared controls

* test(html-player): cover shared-controls source ownership

* feat(html-player): pass shared-controls playback metadata

* docs(player-controls): describe HTML5 shared-controls bridge

* docs(player-controls): clarify HTML5 rollout effect

* fix(html-player): reveal diagnostics from fullscreen

* fix(html-player): defer HLS event resolution

* refactor(html-player): isolate video element session

libs/ui/playback/tsconfig.lib.json

@@ -8,5 +8,9 @@
         "types": []
     },
     "include": ["src/**/*.ts"],
-    "exclude": ["src/**/*.spec.ts", "src/**/*.test.ts"]
+    "exclude": [
+        "src/**/*.spec.ts",
+        "src/**/*.test.ts",
+        "src/**/*.spec-fixtures.ts"
+    ]
 }