fix(playback): route non-HLS containers to the native source path (#1510)

The HTML5 player chose its engine by exclusion: anything that was not
mpd/ts/mp4 went to hls.js, so .mkv (the default Xtream series/VOD
container), .webm, .avi, .mov and .m4v were fed to hls.js as manifests.
hls.js raised a manifest error and the player showed the network/provider
diagnostic over media Chromium plays natively.

Add resolvePlaybackUrlSourceKind() to @iptvnator/playback/util as the one
URL-to-engine rule (mpd -> dash, m3u8/m3u -> hls, ts/m2ts/extension-less
-> mpegts, everything else -> native) and read it from both the HTML5
player and ArtPlayer's getArtPlayerVideoType(), so the two engines agree.
ArtPlayer serves every native container through a single
ART_PLAYER_NATIVE_SOURCE_TYPE custom type, keeping the source session the
owner of teardown and controls binding. The HTML5 native <source> carries
the video/mp4 hint only for MP4-family files: a hint the browser's
canPlayType() rejects makes it skip the source, and Chromium demuxes
containers it does not advertise there.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

docs/architecture/embedded-inline-playback.md

@@ -635,12 +635,25 @@ video.
 
 URL extension metadata is filtered before diagnostics and player selection use it. Web script extensions such as `.php` are not shown as stream containers; explicit media query metadata such as `extension=ts` or `format=m3u8` is preferred when present.
 
+The HTML5 player and ArtPlayer choose their source engine from one URL rule,
+`resolvePlaybackUrlSourceKind()` in `@iptvnator/playback/util`, which maps the
+normalized media extension to `dash` (`mpd`), `hls` (`m3u8`/`m3u`), `mpegts`
+(`ts`, `m2ts`, and extension-less proxy/script URLs) or `native` (every other
+container: `mkv`, `webm`, `mp4`, `avi`, `mov`, `m4v`, audio files). hls.js
+therefore only ever receives HLS manifests; it used to be handed every
+unlisted container and raised a manifest error over media Chromium plays by
+itself. ArtPlayer serves the `native` kind through a single
+`ART_PLAYER_NATIVE_SOURCE_TYPE` custom type so `ArtPlayerSourceSession` keeps
+owning engine teardown and controls binding; the HTML5 player appends one
+`<source>` whose `video/mp4` MIME hint is set only for MP4-family files, since
+a hint the browser's `canPlayType()` rejects makes it skip the source
+(`resolveNativeSourceMimeType()`).
+
 MKV sources are attempted through Chromium's native Matroska path. Video.js
 receives `video/matroska` for `.mkv` URLs and explicit query metadata such as
-`extension=mkv` or `container=mkv`; ArtPlayer and HTML5 continue to use their
-native video paths. This is container support rather than a universal codec
-guarantee: native source or decode failures still produce a diagnostic whose
-ranked actions may include MPV/VLC.
+`extension=mkv` or `container=mkv`. This is container support rather than a
+universal codec guarantee: native source or decode failures still produce a
+diagnostic whose ranked actions may include MPV/VLC.
 
 Portal VOD and episode payloads with `contentInfo` are treated as non-live by the inline players unless `isLive` is explicitly set. If Chromium leaves the underlying MediaSource duration at `Infinity` for a finite TS VOD, the Video.js wrapper normalizes its UI duration from the finite `seekable` or `buffered` range. Embedded MPV uses the same live decision rule and shows an unknown duration placeholder for VOD/episode snapshots until MPV reports a finite duration. This removes the misleading `LIVE` control state without changing stream decoding, diagnostics, or external fallback behavior.
 

docs/architecture/m3u-playlist-module.md

@@ -1037,8 +1037,9 @@ player in settings.
   because those players never receive its keys.
   Channels with `drm.supported === false` emit a `DrmOrEncryption` diagnostic
   with a fixed safe detail string and without starting an engine.
-- HTML5 player: `extension === 'mpd'` branch in `playChannel()`. ArtPlayer:
-  `customType.mpd` in `ArtPlayerSourceSession`. Shared-controls bridge:
+- HTML5 player: the `dash` branch of `playChannel()` (source kind from the
+  shared `resolvePlaybackUrlSourceKind()`). ArtPlayer: `customType.mpd` in
+  `ArtPlayerSourceSession`. Shared-controls bridge:
   `WebVideoControlsSource` kind `'shaka'` + `WebVideoShakaControls`
   (audio/text tracks via the Shaka 5 API — selecting a text track shows it,
   `selectTextTrack(null)` hides).