Add the real FreeRDP3 RDP backend that loads libfreerdp3.dll at runtime
via syscall.NewLazyDLL (no CGO required). The Windows implementation
(freerdp_windows.go) calls FreeRDP3 functions for instance lifecycle,
settings configuration, input forwarding, and event handling. A stub
(freerdp_stub.go) compiles on non-Windows platforms and returns errors,
keeping macOS/Linux development and tests working. A factory function
(freerdp_factory.go) selects the right backend based on runtime.GOOS,
and app.go now uses NewProductionBackend instead of always using mock.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Add RDPService with session lifecycle management (connect, disconnect,
input forwarding, frame retrieval) using an injected backend factory.
Implement MockBackend that generates animated test frames with a
blue-purple gradient, bouncing color-cycling rectangle, pulsing circle,
and grid overlay for canvas renderer verification on macOS without
FreeRDP. The real FreeRDP purego bindings are deferred to Windows.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Define the RDPBackend interface, RDPConfig, and FrameUpdate types that
abstract FreeRDP behind a pluggable backend. Add PixelBuffer for shared
RGBA frame management with partial-update support and dirty tracking.
Implement full 104-key US keyboard scancode map (JS KeyboardEvent.code
to RDP hardware scancodes) with extended-key detection helpers and
mouse event flag constants matching MS-RDPBCGR.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
