Implement Tuner v1 — Go backend, React frontend, Docker setup

- Go backend: REST API, M3U parser, FFmpeg/MediaMTX process manager
- React/Vite frontend: HLS player, admin panel, channel browser (dark theme)
- MediaMTX config for RTMP ingest + HLS output
- Multi-stage Dockerfile (Go + Bun + Alpine runtime)
- docker-compose.yml for single-container deployment
- Sample M3U playlist with test streams

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

data/playlist.m3u

@@ -0,0 +1,13 @@
+#EXTM3U
+
+#EXTINF:-1 tvg-name="Big Buck Bunny" tvg-logo="https://peach.blender.org/wp-content/uploads/bbb-splash.png" group-title="Test Streams",Big Buck Bunny
+https://test-streams.mux.dev/x36xhzz/x36xhzz.m3u8
+
+#EXTINF:-1 tvg-name="Sintel" tvg-logo="" group-title="Test Streams",Sintel
+https://bitdash-a.akamaihd.net/content/sintel/hls/playlist.m3u8
+
+#EXTINF:-1 tvg-name="Tears of Steel" tvg-logo="" group-title="Test Streams",Tears of Steel
+https://demo.unified-streaming.com/k8s/features/stable/video/tears-of-steel/tears-of-steel.ism/.m3u8
+
+#EXTINF:-1 tvg-name="NASA Live" tvg-logo="" group-title="Live",NASA Live
+https://ntsc-tv.nasa.gov/nasatv/HLS/ntv1.m3u8