build: burn down the mobile and TV detekt baselines #292

Parent: #52 · Follow-up to #286

detekt never analyzed the mobile and TV code. Its default sources are src/main and src/test, and that code lived in app/src/mobile, app/src/tv, testMobile and testTv. The app split moves it into each module's main and test, and records the existing findings in mobile/detekt-baseline.xml (115 entries) and tv/detekt-baseline.xml (70 entries). New code must pass; these baselines should only shrink.

Findings at the split:

• mobile: 37 MaxLineLength, 19 CyclomaticComplexMethod, 14 ReturnCount, 8 MagicNumber, plus a handful each of LongParameterList, LongMethod, TooManyFunctions, LargeClass, ComplexCondition, SwallowedException
• tv: 25 MaxLineLength, 17 CyclomaticComplexMethod, plus smaller counts of LongParameterList, MagicNumber, ReturnCount, LongMethod, TooManyFunctions, LargeClass, ComplexCondition
• Hot spots: MobileFileShareService.kt (13), TvPlayerScreen.kt (11), MobileDownloadEngine.kt (6), TvPlayerTracks.kt (6)

Acceptance

• MaxLineLength entries fixed (mechanical).
• Each remaining entry is either fixed or kept with a @Suppress that names the constraint, for example a Compose state when that cannot split.
• Both baselines deleted.

Written by an agent (Claude Code, Opus 5.5)