Add runtime script management with Home Assistant integration

Features:
- Runtime script CRUD operations (create, update, delete)
- Thread-safe ConfigManager for YAML updates
- WebSocket notifications for script changes
- Web UI script management interface with full CRUD
- Home Assistant auto-reload on script changes
- Client-side position interpolation for smooth playback
- Include command field in script list API response

Technical improvements:
- Added broadcast_scripts_changed() to WebSocket manager
- Enhanced HA integration to handle scripts_changed messages
- Implemented smooth position updates in Web UI (100ms interval)
- Thread-safe configuration updates with file locking

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

media_server/services/websocket_manager.py

@@ -68,6 +68,12 @@ class ConnectionManager:
         for ws in disconnected:
             await self.disconnect(ws)
 
+    async def broadcast_scripts_changed(self) -> None:
+        """Notify all connected clients that scripts have changed."""
+        message = {"type": "scripts_changed", "data": {}}
+        await self.broadcast(message)
+        logger.info("Broadcast sent: scripts_changed")
+
     def status_changed(
         self, old: dict[str, Any] | None, new: dict[str, Any]
     ) -> bool: