feat: add permission screen shown before main screen

lib/bridge/location_bridge.dart

@@ -92,4 +92,16 @@ class LocationBridge {
       return [];
     }
   }
+
+  static Future<bool> openBatteryOptimizationSettings() async {
+    try {
+      final result = await _methodChannel.invokeMethod<bool>(
+        'openBatteryOptimizationSettings',
+      );
+      return result ?? false;
+    } on PlatformException catch (e) {
+      debugPrint('Failed to open battery settings: ${e.message}');
+      return false;
+    }
+  }
 }