feat(android): PlayerFactory + CacheConfig + Media3 1.10.1 bump (M8 phase 6.1)

First Media3 wiring. PlayerFactory builds the process-singleton
ExoPlayer with our shared OkHttp + SimpleCache chain; the
MinstrelPlayerService (Phase 6.2) calls build() in onCreate.

Chain shape:
  ExoPlayer
    .setMediaSourceFactory(DefaultMediaSourceFactory + CacheDataSource)
    .setAudioAttributes(USAGE_MEDIA + CONTENT_TYPE_MUSIC, focus=true)
    .setHandleAudioBecomingNoisy(true)

  CacheDataSource
    .setCache(SimpleCache(audio_cache dir, LRU evictor, Room standalone DB))
    .setUpstreamDataSourceFactory(OkHttpDataSource over shared OkHttp)
    .setCacheWriteDataSinkFactory(CacheDataSink full-fragment)

Built-in audio focus + becoming-noisy handling — Media3 owns these so
no audio_session-equivalent code path is needed (the Flutter app had
~40 LOC for the same; here it's three lines of config).

simpleCache exposed as a PlayerFactory val so the AudioCacheEviction
Worker (Phase 12.3) can call removeSpan() during 2-bucket eviction.

CacheConfig (defaults 200MiB liked + 150MiB rolling) — Phase 11
Settings will let users override.

Bumped Media3 1.4.1 -> 1.10.1 (current stable, AGP 9 + Kotlin 2.3
friendly, MediaSessionService now extends LifecycleService which
makes 6.2's lifecycle-aware patterns cleaner). Breaking changes
between 1.4 and 1.10 don't affect our usage (DRM, FrameExtractor,
ChannelMixingMatrix — we use none).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

android/gradle/libs.versions.toml

@@ -21,7 +21,7 @@ kotlinx-serialization = "1.7.3"
 kotlinx-coroutines = "1.9.0"
 kotlinx-datetime = "0.6.1"
 kotlinx-serialization-converter = "1.0.0"
-media3 = "1.4.1"
+media3 = "1.10.1"
 coil = "3.0.0-rc02"
 timber = "5.0.1"
 work = "2.10.0"