Expose PluriWave to Android Auto (projected) as a media app:
- Declare car media support (automotive_app_desc.xml + manifest meta-data)
so Android Auto discovers the existing MediaBrowserService.
- New navegacion_auto.dart: ConstructorArbolAuto builds the browse tree
(Favoritos / Todas las emisoras / Mis emisoras, 50-item cap, stable
emisora:<id> media ids), reproducirPorMediaId routes a car tap to the
existing playMediaItem pipeline, FuenteEmisorasAutoLocal serves the tree
cold-start-safe (local favorites/custom stations before Flutter UI runs).
- PluriWaveAudioHandler overrides getChildren/getMediaItem/playFromMediaId
as thin delegations; playback pipeline untouched.
- EstadoRadio pushes live station snapshots to the browse source and
reconciles the selected station when playback starts from the car.
- Every playable item ships title + artUri; stations without logo fall
back to a bundled default art (android.resource://).
Tests: 52/52 green (10 new navegacion_auto, 2 new estado_radio, plus
audio safety-net suites). Handler overrides and native XML are
static-review-only (no Android build env). Size exception approved for a
single reviewable commit.
Javier Bautista Fernández
35bb180612