Return the keyboard on Remote shortcuts and announce focus changes

During remote focus a Remote shortcut now ends capture, like F11,
instead of running its command, which would race with the focus change.
The reader announces when the keyboard starts and stops controlling the
remote computer, and the consent wording names the F11 escape.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/app/tentacle_remote_capture.go

@@ -105,8 +105,10 @@ func (runtime *tentacleRuntime) start_remote_capture(ctx context.Context, sessio
 				id, stream, err := capture.BeginRemoteCapture(request.Context, prefix)
 				if err != nil {
 					_ = session.PublishRemoteFocus(request.Lease, tentaclewire.RemoteFocusLocal, "unavailable")
+					runtime.report("Remote keyboard control is unavailable.")
 					continue
 				}
+				runtime.report("Keyboard controls the remote computer. Press F11 to return.")
 				active, lease, events, leaseDone = id, request.Lease, stream, request.Context.Done()
 				if session.PublishRemoteFocus(lease, tentaclewire.RemoteFocusRemote, "requested") != nil {
 					end()
@@ -118,6 +120,7 @@ func (runtime *tentacleRuntime) start_remote_capture(ctx context.Context, sessio
 				}
 				if event.Ended != "" {
 					_ = session.PublishRemoteFocus(lease, tentaclewire.RemoteFocusLocal, event.Ended)
+					runtime.report("Keyboard returned to this computer.")
 					continue
 				}
 				key := tentaclewire.RemoteCapturedKey{Code: int(event.Key.Code), Name: event.Key.Name, Pressed: event.Key.Pressed, Repeat: event.Key.Repeat}

internal/app/tentacle_remote_consent.go

@@ -118,7 +118,7 @@ func remote_consent_form(id, role string, grants []string) interaction.Form {
 	labels := map[string]string{
 		"output-observe":     "Share local reader output with the remote controller",
 		"remote-present":     "Present output from the controlled computer",
-		"keyboard-capture":   "Forward local keyboard input to the controlled computer",
+		"keyboard-capture":   "Forward local keyboard input to the controlled computer while remote focus is on. Press F11 to return to this computer",
 		"keyboard-inject":    "Allow the remote controller to type on this computer",
 		"clipboard-exchange": "Allow receiving clipboard text; send only on explicit local request",
 		"braille-stream":     "Exchange remote braille cells and supported display gestures",