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>

docker-compose.yml

@@ -0,0 +1,13 @@
+services:
+  tuner:
+    build: .
+    ports:
+      - "1935:1935"
+      - "8080:8080"
+      - "8888:8888"
+    volumes:
+      - ./data/playlist.m3u:/data/playlist.m3u:ro
+    environment:
+      RESTREAMER_PORT: "8080"
+      PLAYLIST_PATH: "/data/playlist.m3u"
+    restart: unless-stopped