feat: show 'The AI stopped Screen Operator' toast when AI ends turn in background

The native toast (UiStringsConfig id toast_ai_stopped_app, used by
PhotoReasoningCommandUiNotifier) existed but was never triggered from the
WebView. It now fires through the generic WebViewBridge.showToast channel
when the app is not in the foreground and the AI ends the turn on its own:

- response without any recognized command (unless a popUp() question is
  still awaiting the user's answer - a pause for input, not a stop)
- completed()

Toast text honors ui-strings-overrides.json like the native call site.

Author: Android-PowerUser

index.html

@@ -3851,6 +3851,36 @@
   _termuxSessionArmed = false;
 }
 
+/* ── "The AI stopped Screen Operator" background toast ───── */
+// The toast itself is the native one (PhotoReasoningCommandUiNotifier / UiStringsConfig id
+// "toast_ai_stopped_app"), reached through the generic WebViewBridge.showToast channel - the
+// WebView only decides WHEN it fires: the AI ended the turn on its own (a response without
+// any command, or completed()) while the app is not in the foreground, so the in-page
+// generation-state change cannot be seen.
+const _AI_STOPPED_TOAST_ID = 'toast_ai_stopped_app';
+
+function _aiStoppedToastText() {
+  // Mirror of UiStringsConfig.get(id, default): an optional ui-strings-overrides.json value
+  // wins, non-blank strings only, otherwise the built-in default documented in
+  // DEFAULT_UI_STRINGS.
+  const fallback = DEFAULT_UI_STRINGS[_AI_STOPPED_TOAST_ID];
+  try {
+    if (getInAndroid() && typeof Android.getUiStringsOverrides === 'function') {
+      const override = JSON.parse(Android.getUiStringsOverrides() || '{}')[_AI_STOPPED_TOAST_ID];
+      if (typeof override === 'string' && override.trim()) return override;
+    }
+  } catch(e) { /* fall through to built-in default */ }
+  return fallback;
+}
+
+function _showAiStoppedToastInBackground() {
+  if (!getInAndroid()) return;
+  try {
+    if (Bridge.isAppInForeground()) return;
+    Bridge.showToast(_aiStoppedToastText(), false);
+  } catch(e) { console.warn('[ScreenOperator] AI-stopped toast failed', e); }
+}
+
 async function _executeCommandsFromResponse(text) {
   _stopExecution = false;
   // Reset batch answer collection for each new AI response so answers from a previous
@@ -3868,6 +3898,9 @@
     if (window.onGenerationStateChanged) window.onGenerationStateChanged(false, false);
     // Clear any leftover commands bubble from the previous message
     if (window.onCommandStatus) window.onCommandStatus('');
+    // The AI stopped the turn - unless a popUp() question from this response is still
+    // waiting for the user's answer (that is a pause for input, not a stop).
+    if (!_activeAiQuestion && !_aiQuestionQueue.length) _showAiStoppedToastInBackground();
     return;
   }
 
@@ -3980,6 +4013,7 @@
       _stopExecution = true;
       generationRunning = false;
       if (window.onGenerationStateChanged) window.onGenerationStateChanged(false, false);
+      _showAiStoppedToastInBackground();
       break;
     default:
       console.log('[ScreenOperator] Unknown command type:', cmd.type, cmd);