refactor(chromecast): [PKG-CAST-04] preserve published types and add runtime entry

packages/artplayer-plugin-chromecast/README.md

@@ -6,6 +6,76 @@ Chromecast plugin for ArtPlayer
 
 [https://artplayer.org](https://artplayer.org/?libs=./uncompiled/artplayer-plugin-chromecast/index.js&example=chromecast)
 
+## Usage
+
+```js
+import Artplayer from 'artplayer'
+import artplayerPluginChromecast from 'artplayer-plugin-chromecast'
+
+const art = new Artplayer({
+  container: '.artplayer-app',
+  url: 'https://example.com/video.mp4',
+  plugins: [artplayerPluginChromecast({
+    onStateChange(state) {
+      console.log(state)
+    },
+    onError(error) {
+      console.error(error)
+    },
+  })],
+})
+```
+
+Replace the example URL with media reachable by your receiver. SDK loading starts
+when the Cast control is clicked. Use a supported Chrome sender on HTTPS and an
+available Cast receiver; loading the demo or a local video alone does not verify
+receiver playback. The optional `url`, `sdk`, `icon` and `mimeType` override the
+media URL, SDK script URL, control HTML and inferred media type respectively.
+Callbacks are `onStateChange`, `onCastAvailable`, `onCastStart` and `onError`.
+
+## TypeScript compatibility
+
+The root and `legacy` declarations preserve the latest published 1.1.0 type shape:
+a required options object and a synchronous name-only registration type. JavaScript
+registration is actually asynchronous. New TypeScript consumers can use the
+additive `artplayer-plugin-chromecast/runtime` entry for precise callbacks and a
+`Promise<RuntimeResult>`, without loading another implementation:
+
+```ts
+import artplayerPluginChromecast from 'artplayer-plugin-chromecast/runtime'
+import type { RuntimeOption } from 'artplayer-plugin-chromecast/runtime'
+
+const options: RuntimeOption = {
+  onStateChange(state) {
+    // disconnected | connecting | connected | disconnecting
+    console.log(state, this.url)
+  },
+  onError(error) {
+    // unknown: SDK and user callbacks can throw arbitrary values.
+    console.error(error)
+  },
+}
+const register = artplayerPluginChromecast(options)
+// In an existing ArtPlayer setup, register(art) returns Promise<RuntimeResult>.
+// Supply register once through the player's plugins option.
+```
+
+The resolved result contains `name`, `getCastState(): string | null` and
+`isCasting(): boolean`. The raw state is initially null and differs from the
+normalized callback state. A retained session does not prove successful playback.
+
+Version 1.0.0 used `export =` declarations and a CommonJS `.default` factory;
+1.1.0 changed to a default declaration and direct CommonJS factory. Those old type
+shapes cannot both describe the same root. The candidate keeps 1.1.0's root type
+and supports both historical JavaScript factory forms. For older `import = require`
+TypeScript consumers, migrate to `import cast = require('artplayer-plugin-chromecast/runtime')`.
+Native ESM consumers should use the runtime default import shown above. Root
+NodeNext namespace typing retains 1.1.0's existing behavior; its direct ESM default
+call was already a type error. The runtime entry fixes that use without changing
+the old root's module replacement contracts.
+
+Maintenance and validation details are in [ARCHITECTURE.md](ARCHITECTURE.md).
+
 ## License
 
 MIT © Harvey Zhao