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>

mediamtx.yml

@@ -0,0 +1,30 @@
+###############################################
+# MediaMTX configuration for Tuner
+###############################################
+
+# Logging
+logLevel: info
+logDestinations: [stdout]
+
+# RTMP server (ingest from OBS / FFmpeg)
+rtmp: yes
+rtmpAddress: :1935
+
+# HLS server (output to viewers)
+hls: yes
+hlsAddress: :8888
+hlsAlwaysRemux: yes
+hlsSegmentCount: 3
+hlsSegmentDuration: 1s
+hlsAllowOrigin: '*'
+
+# Disable unused protocols
+rtsp: no
+webrtc: no
+srt: no
+record: no
+
+# Path configuration
+paths:
+  live/stream:
+    source: publisher