Add on-device webcam capture to the experimental Android-TV build. Desktop
captures webcams via OpenCV (no Chaquopy/Android wheel); this adds a push-based
AndroidCameraEngine that plugs into the same selection path desktop uses
(capture template engine_type="android_camera" + display_index, HAS_OWN_DISPLAYS).
A Kotlin CameraBridge (Camera2) enumerates cameras and opens them on demand —
only while a capture source is active, driven Python->Kotlin via a guarded jclass
singleton (BleBridge pattern) — converts each frame YUV_420_888->RGB, and pushes
RGB bytes into a module-level queue mirroring mediaprojection_engine.py. Cameras
surface as selectable displays like the desktop OpenCV engine; the data-driven
capture-template UI is unchanged. No new Python deps; no new Gradle deps
(Camera2 is in-platform).
Engine: ENGINE_PRIORITY=0 (never auto-selected over MediaProjection=100; explicit
engine_type only). Single-camera ownership is serialized with a lock + ref-count
(same-camera streams attach, different-camera refused, last release stops),
mirroring the desktop CameraEngine guard.
Permission: CAMERA requested at capture-start, gated on FEATURE_CAMERA_ANY so
camera-less TV boxes never prompt; graceful degradation when denied. The service
is promoted with the camera FGS type (+ FOREGROUND_SERVICE_CAMERA) only when
CAMERA is already granted, so backgrounded capture keeps working without risking
a failed startForeground on camera-less boxes (camera can't ride the
MediaProjection token the way audio playback capture does).
Reviewed via multi-agent adversarial pass (13 findings -> 4 fixed: device leak on
session-failure, multi-stream collision, camera FGS type, i18n key; 9 refuted).
Tests: 18 new desktop-CI tests (no device needed); full suite 1883 passed.
Verified: assembleDebug BUILD SUCCESSFUL, ruff clean.
Docs: ANDROID-REVIEW/android-webcam-capture-plan.md (design), updated
android-missing-functionality.md + README feature table + en/ru/zh locales.
alexei.dolgolyov
4bf3fe65db