Fix Telegram viewport and SVG avatars

lib/auth/telegram_session_stub.dart

@@ -10,6 +10,8 @@ void saveMapflowSessionToken(String token) {}
 
 void clearMapflowSession() {}
 
+void configureTelegramWebApp() {}
+
 void openExternalUrl(String url) {}
 
 void reloadApp() {}

lib/auth/telegram_session_web.dart

@@ -5,13 +5,28 @@ import 'package:web/web.dart' as web;
 const telegramLoginStorageKey = 'mapflow.telegramLoginData';
 const mapflowSessionStorageKey = 'mapflow.sessionToken';
 
-@JS('window.Telegram.WebApp.initData')
-external JSString? get _telegramInitData;
+@JS('Telegram')
+external _Telegram? get _telegram;
+
+extension type _Telegram(JSObject _) implements JSObject {
+  @JS('WebApp')
+  external _TelegramWebApp? get webApp;
+}
+
+extension type _TelegramWebApp(JSObject _) implements JSObject {
+  external JSString? get initData;
+  external void ready();
+  external void expand();
+  external bool isVersionAtLeast(String version);
+  external void disableVerticalSwipes();
+}
 
 @JS('JSON.stringify')
 external JSString _jsonStringify(JSAny? value);
 
-String telegramInitData() => _telegramInitData?.toDart ?? '';
+_TelegramWebApp? get _webApp => _telegram?.webApp;
+
+String telegramInitData() => _webApp?.initData?.toDart ?? '';
 
 String telegramLoginData() =>
     web.window.localStorage.getItem(telegramLoginStorageKey) ?? '';
@@ -38,6 +53,19 @@ void clearMapflowSession() {
   web.window.localStorage.removeItem(telegramLoginStorageKey);
 }
 
+void configureTelegramWebApp() {
+  final webApp = _webApp;
+  if (webApp == null) {
+    return;
+  }
+
+  webApp.ready();
+  webApp.expand();
+  if (webApp.isVersionAtLeast('7.7')) {
+    webApp.disableVerticalSwipes();
+  }
+}
+
 void openExternalUrl(String url) {
   web.window.location.assign(url);
 }