Initial commit: Camera Viewer with Frigate alerts

Features:
- 8-camera WebRTC grid using go2rtc
- MQTT subscription to Frigate events
- Auto-fullscreen on person detection (Front_Porch)
- SSE for real-time browser updates
- Touch-friendly tablet interface
- Wake lock to keep screen on
- Auto-dismiss after 30 seconds

.gitignore

@@ -0,0 +1,9 @@
+# Python
+__pycache__/
+*.py[cod]
+venv/
+.env
+
+# IDE
+.vscode/
+.idea/