Fix LED color events and improve screenshot capture

- Fix LED color publisher: uncomment display_colors_tx.send() to enable LED color events
- Replace rust_swift_screencapture with screen-capture-kit for better macOS compatibility
- Add bounds checking in LED color processing to prevent array index errors
- Update screenshot manager to use CGDisplay as fallback implementation
- Fix frontend screenshot URL protocol to use ambient-light://
- Add debug logging for LED color events in frontend
- Remove debug logs that were added for troubleshooting
- Update dependencies and remove CMake-dependent paho-mqtt temporarily

This resolves the issue where LED color events were not being sent to the frontend,
enabling real-time LED color visualization in the UI.

src-tauri/tauri.conf.json

@@ -16,6 +16,13 @@
       "shell": {
         "all": false,
         "open": true
+      },
+      "protocol": {
+        "all": true,
+        "asset": true,
+        "assetScope": [
+          "**"
+        ]
       }
     },
     "bundle": {