[devopvoid]

• JavaFxCameraExample sends the camera from one peer to another in the same process, and shows the mirrored preview beside the received video in two JavaFX VideoViews.
• Handlers run on the JavaFX Application Thread via Platform::runLater. A dropdown switches the camera while it's being sent, and the window shows the connection state and the encoded resolution and frame rate.
• It starts with Platform.startup rather than an Application subclass, so it also runs from the class path with mvn exec:java.
• webrtc-examples now depends on webrtc-java-javafx and javafx-controls 17.0.20.
• The examples page, the client API guide and the design doc mention the example.