feat(clients/windows): GPU picker, disconnect shortcut, richer stream HUD

- Settings gains a GPU selector (shown only on multi-GPU boxes): the picked
  DXGI adapter drives decode + present, persisted as Settings.adapter and
  applied at the next stream - gpu.rs now caches the shared device keyed by
  the resolved preference (env PUNKTFUNK_ADAPTER > Settings > the window's
  monitor's adapter) so a change needs no app restart.
- Ctrl+Alt+Shift+D disconnects the session (consumed locally, captured or
  released): the hook releases capture and trips the session stop flag,
  plumbed through the stream-page handoff; the pump winds down and the UI
  navigates back to the host list.
- Stream HUD extended: codec chip (HEVC/H.264/AV1), display-side line from
  the render thread (presents/s + capture-to-decoded vs capture-to-on-glass
  p50), session line (host name, duration, network-lost frames, skipped
  backlog frames), and both shortcut hints incl. the new disconnect.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

clients/windows/src/app/connect.rs

@@ -250,7 +250,8 @@ fn connect_with(
                 }
                 gamepad.attach(connector.clone());
                 *shared.stats.lock().unwrap() = Stats::default(); // clear any prior session's numbers
-                *shared.handoff.lock().unwrap() = Some((connector, handle.frames.clone()));
+                *shared.handoff.lock().unwrap() =
+                    Some((connector, handle.frames.clone(), handle.stop.clone()));
                 ss.call(Screen::Stream);
             }
             SessionEvent::Failed {