Tuner v1: HLS pipeline with playback/ingest modes

FFmpeg -> MediaMTX -> HLS relay with runtime-configurable modes:
- PLAYBACK_MODE: standard (mpegts), fmp4 (HEVC), llhls
- INGEST_MODE: rtmp, rtsp
- INGEST_AUDIO_MODE: aac, copy
- Hourly playlist auto-refresh from upstream URL
- Fullscreen video UI with collapsible sidebar, upstream-down banner
- Same-origin HLS proxy for HTTPS deployments

Tagged as the last HLS-based version before the mpegts.js (v2) rework.

mediamtx.yml

@@ -15,11 +15,15 @@ rtmp: yes
 rtmpAddress: :1935
 
 # HLS server (output to viewers)
+# Note: hlsVariant / segment / part durations are overridden at runtime by the
+# backend via MTX_HLS* environment variables, based on PLAYBACK_MODE
+# (standard = mpegts, fmp4 = fragmented MP4, llhls = lowLatency).
 hls: yes
 hlsAddress: :8888
 hlsAlwaysRemux: yes
+hlsVariant: mpegts
 hlsSegmentCount: 7
-hlsSegmentDuration: 1s
+hlsSegmentDuration: 2s
 hlsAllowOrigin: '*'
 
 # RTSP server (used internally for FFmpeg → MediaMTX push, supports HEVC)