[feat] unify Windows unattended hosting with shared device identity

Keep RTC connections in the persistent SYSTEM host and attach GUI session features through an authenticated local channel. Share device credentials, settings and trusted devices, and use the service for Windows boot startup.

Unify normal and secure desktop capture fallback, recover virtual displays, and coordinate cursor ownership across desktop transitions. Update localization, documentation and the MiniRTC dependency.

Validated with git diff --check and localization catalog JSON parsing. Builds and runtime tests were not run.

apps/desktop/src/gui/application/gui_application.h

@@ -58,6 +58,9 @@ private:
   void BindStreamCallbacks();
   void BindServerCallbacks();
   void Tick();
+#ifdef _WIN32
+  void TickLocalHost();
+#endif
   void PollUpdateCheck();
   void ShareLocalCursorState();
   bool RequestPasswordChange(const std::string &password);