간편 로그인 · 성운/행성 생성을 아래에서 올라오는 전환으로

app/lib/features/auth/login_screen.dart

@@ -6,6 +6,7 @@ import '../../core/firebase/firebase_boot.dart';
 import '../../core/i18n/app_locale.dart';
 import '../../core/theme/tokens.dart';
 import '../../core/ui/app_icons.dart';
+import '../../core/ui/sheet_route.dart';
 import 'auth.dart';
 import 'auth_repository.dart';
 import 'signup_screens.dart';
@@ -101,9 +102,9 @@ class _LoginScreenState extends State<LoginScreen> {
 
   void _open({required bool signUp}) {
     Navigator.of(context).push(
-      MaterialPageRoute<void>(
-        // 명세 `510:86374` 「닫기 — 아래 방향 Move Out 으로 이전 화면」 — 아래에서 올라오는 전체 화면.
-        fullscreenDialog: true,
+      // 명세 `510:86374` 「닫기 — 아래 방향 Move Out 으로 이전 화면」 — 아래에서 올라오는 전체 화면.
+      // fullscreenDialog 만으로는 Android 에서 페이드 · 확대로 열렸다(10/6 실기기 E-5).
+      SheetRoute<void>(
         builder: (_) => SimpleLoginScreen(auth: widget.auth, signUp: signUp),
       ),
     );
@@ -248,8 +249,7 @@ class _SimpleLoginScreenState extends State<SimpleLoginScreen> {
 
   void _switchMode() {
     Navigator.of(context).pushReplacement(
-      MaterialPageRoute<void>(
-        fullscreenDialog: true,
+      SheetRoute<void>(
         builder: (_) =>
             SimpleLoginScreen(auth: widget.auth, signUp: !widget.signUp),
       ),

app/lib/features/auth/onboarding_screens.dart

@@ -5,6 +5,7 @@ import '../../core/i18n/app_locale.dart';
 import '../../core/push/push_messaging.dart';
 import '../../core/theme/tokens.dart';
 import '../../core/ui/app_icons.dart';
+import '../../core/ui/sheet_route.dart';
 import '../home/coach_mark.dart';
 import '../home/home_data.dart';
 import '../home/nebula_create_screen.dart';
@@ -259,7 +260,7 @@ class _OnboardingFlowState extends State<OnboardingFlow> {
         }),
         onCreateNebula: () async {
           final created = await Navigator.of(context).push<String>(
-            MaterialPageRoute(
+            SheetRoute(
               builder: (_) => NebulaCreateScreen(repository: widget.home),
             ),
           );