fix: iPad modal auto-dismiss on iPadOS 26.1+

close #224, credits to @Jon-Salmon for the workaround: https://github.com/flutter/flutter/issues/175606#issuecomment-3453392532

lib/main.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'package:flutter/gestures.dart';
 import 'dart:io' show Platform;
 import 'package:window_manager/window_manager.dart';
 import 'package:provider/provider.dart';
@@ -39,8 +40,26 @@ import 'utils/language_codes.dart';
 import 'i18n/strings.g.dart';
 import 'focus/input_mode_tracker.dart';
 
+// Workaround for Flutter bug #177992: iPadOS 26.1+ misinterprets fake touch events
+// at (0,0) as barrier taps, causing modals to dismiss immediately.
+// Remove when Flutter PR #179643 is merged.
+bool _zeroOffsetPointerGuardInstalled = false;
+
+void _installZeroOffsetPointerGuard() {
+  if (_zeroOffsetPointerGuardInstalled) return;
+  GestureBinding.instance.pointerRouter.addGlobalRoute(_absorbZeroOffsetPointerEvent);
+  _zeroOffsetPointerGuardInstalled = true;
+}
+
+void _absorbZeroOffsetPointerEvent(PointerEvent event) {
+  if (event.position == Offset.zero) {
+    GestureBinding.instance.cancelPointer(event.pointer);
+  }
+}
+
 void main() async {
   WidgetsFlutterBinding.ensureInitialized();
+  _installZeroOffsetPointerGuard(); // Workaround for iPadOS 26.1+ modal dismissal bug
 
   // Initialize settings first to get saved locale
   final settings = await SettingsService.getInstance();