refactor(ambilight): [PKG-AMBILIGHT-03] split typed lifecycle and recover native canvas sampling

packages/artplayer-plugin-ambilight/README.md

@@ -2,6 +2,13 @@
 
 ambilight plugin for ArtPlayer
 
+`start()` and `stop()` are synchronous. The plugin starts on the player's `ready`
+event; `stop()` retains its last colors. Destroying the player removes the plugin's
+grid and frame loop, and previously retained methods then do nothing. Canvas read
+failures are skipped and retried, allowing a later readable source to recover.
+
+Internal modules and compatibility tests are documented in [ARCHITECTURE.md](ARCHITECTURE.md).
+
 ## Demo
 
 [https://artplayer.org](https://artplayer.org/?libs=./uncompiled/artplayer-plugin-ambilight/index.js&example=ambilight)