feat: implement splash and onboarding flows, update app assets, and add project design documentation

apps/rider/lib/features/auth/cubit/auth_cubit.dart

@@ -8,13 +8,34 @@ class AuthCubit extends Cubit<AuthState> {
   AuthCubit(this._repo) : super(const AuthState());
 
   Future<void> checkAuth() async {
+    final hasToken = await _repo.hasSavedToken();
+    if (hasToken) {
+      final cachedUser = await _repo.getCachedUser();
+      if (cachedUser != null) {
+        emit(state.copyWith(
+          status: AuthStatus.authenticated,
+          user: cachedUser,
+        ));
+      }
+    }
     final user = await _repo.me();
-    emit(state.copyWith(
-      status: user != null ? AuthStatus.authenticated : AuthStatus.unauthenticated,
-      user: user,
-    ));
+    if (user != null) {
+      emit(state.copyWith(
+        status: AuthStatus.authenticated,
+        user: user,
+      ));
+    } else {
+      final hasTokenAfterMe = await _repo.hasSavedToken();
+      if (!hasTokenAfterMe) {
+        emit(state.copyWith(
+          status: AuthStatus.unauthenticated,
+          user: null,
+        ));
+      }
+    }
   }
 
+
   Future<void> sendOtp(String phone) async {
     if (phone.trim().isEmpty) {
       emit(state.copyWith(status: AuthStatus.error, error: 'أدخل رقم الهاتف'));
@@ -43,4 +64,14 @@ class AuthCubit extends Cubit<AuthState> {
     await _repo.logout();
     emit(const AuthState(status: AuthStatus.unauthenticated));
   }
+
+  Future<void> updateName(String name) async {
+    try {
+      emit(state.copyWith(status: AuthStatus.authenticating));
+      final user = await _repo.updateName(name);
+      emit(state.copyWith(status: AuthStatus.authenticated, user: user));
+    } catch (_) {
+      emit(state.copyWith(status: AuthStatus.error, error: 'تعذّر حفظ الاسم'));
+    }
+  }
 }