Add media services: camera, mic, audio, clipboard, usage stats

- CameraService: photo capture, video recording (Camera2 API)
- MicrophoneService: audio recording, voice messages
- AudioPlaybackService: play audio from file/URI/base64
- ClipboardService: copy/paste text and URIs
- UsageStatsService: foreground app, recent apps
- Updated memory/PROJECT_STATUS.md with full status