feat(v0.703): Go Live & Streaming Complet
- Backend: room creation for live streams, permissions CanJoin/CanSend/CanRead for stream rooms
- LiveViewChat: useLiveStreamChat hook, WebSocket connection, stream_id as room
- LiveViewPlayer: real-time viewer count via polling (5s)
- Media Session: seekbackward/seekforward handlers (10s step)
- GoLiveView.stories.tsx: Default, Loading, Error, StreamKeyVisible
- Docs: API_REFERENCE, CHANGELOG, PROJECT_STATE, FEATURE_STATUS, RETROSPECTIVE_V0703
- SCOPE_CONTROL, .cursorrules: update to v0.801
- Archive V0_703_RELEASE_SCOPE.md
63867f1d09