[Feature Request] On-Screen Gamepad Support

1. Client-Side (Browser)
Implement an on-screen virtual joypad and buttons overlay on the screen mirroring web UI.
Detect touch/click events on these virtual buttons and joysticks.
Transmit the controller state changes over the existing WebSocket connection (or WebRTC data channel) to the server.
2. Server-Side (Host)
Receive the controller state payloads from the client.
Use FFI (Foreign Function Interface) bindings to interact with OS-level virtual input device APIs.

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Reference: https://github.com/pthsarmah/streamer