feat: add onboarding flow with visual redesign

Introduce 6-step onboarding screen (Goal → Gender → DOB → Height+Weight
→ Activity → Calories) with per-step accent colors, hero illustration
area (concentric circles + icon), and white card content panel.

Backend user entity and service updated to support onboarding fields
(goal, activity, height, weight, DOB, dailyCalories). Router guards
unauthenticated and onboarding-incomplete users. Profile service and
screen updated to expose language and onboarding preferences.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/internal/domain/user/entity.go

@@ -33,7 +33,7 @@ type UpdateProfileRequest struct {
 	Activity      *string          `json:"activity"`
 	Goal          *string          `json:"goal"`
 	Preferences   *json.RawMessage `json:"preferences"`
-	DailyCalories *int             `json:"-"` // internal, set by service
+	DailyCalories *int             `json:"daily_calories,omitempty"`
 }
 
 // HasBodyParams returns true if any body parameter is being updated

backend/internal/domain/user/service.go

@@ -65,7 +65,12 @@ func (s *Service) UpdateProfile(ctx context.Context, userID string, req UpdatePr
 		goal = req.Goal
 	}
 
-	calories := CalculateDailyCalories(height, weight, age, gender, activity, goal)
+	var calories *int
+	if req.DailyCalories != nil {
+		calories = req.DailyCalories
+	} else {
+		calories = CalculateDailyCalories(height, weight, age, gender, activity, goal)
+	}
 
 	var calReq *UpdateProfileRequest
 	if calories != nil {

client/lib/core/router/app_router.dart

@@ -6,6 +6,9 @@ import '../auth/auth_provider.dart';
 import '../../features/auth/login_screen.dart';
 import '../../features/auth/register_screen.dart';
 import '../../features/home/home_screen.dart';
+import '../../features/onboarding/onboarding_screen.dart';
+import '../../features/profile/profile_provider.dart';
+import '../../shared/models/user.dart';
 import '../../features/products/products_screen.dart';
 import '../../features/products/add_product_screen.dart';
 import '../../features/scan/scan_screen.dart';
@@ -22,10 +25,20 @@ import '../../features/products/product_provider.dart';
 import '../../shared/models/recipe.dart';
 import '../../shared/models/saved_recipe.dart';
 
-// Notifies GoRouter when auth state changes without recreating the router.
+// Notifies GoRouter when auth state or profile state changes.
 class _RouterNotifier extends ChangeNotifier {
   _RouterNotifier(Ref ref) {
-    ref.listen<AuthState>(authProvider, (_, __) => notifyListeners());
+    ref.listen<AuthState>(authProvider, (previous, next) {
+      // Reload profile whenever auth transitions to authenticated.
+      // This handles the case where profileProvider did an initial load before
+      // tokens were available (401 → AsyncError) and needs a fresh load after login.
+      if (next.status == AuthStatus.authenticated &&
+          previous?.status != AuthStatus.authenticated) {
+        ref.read(profileProvider.notifier).load();
+      }
+      notifyListeners();
+    });
+    ref.listen<AsyncValue<User>>(profileProvider, (_, __) => notifyListeners());
   }
 }
 
@@ -41,11 +54,29 @@ final routerProvider = Provider<GoRouter>((ref) {
       final authState = ref.read(authProvider);
       final isLoggedIn = authState.status == AuthStatus.authenticated;
       final isAuthRoute = state.matchedLocation.startsWith('/auth');
+      final isOnboarding = state.matchedLocation.startsWith('/onboarding');
 
       // Show splash until the stored-token check completes.
       if (authState.status == AuthStatus.unknown) return '/loading';
       if (!isLoggedIn && !isAuthRoute) return '/auth/login';
-      if (isLoggedIn && isAuthRoute) return '/home';
+
+      if (isLoggedIn) {
+        // Reading profileProvider triggers its lazy initialization (load() in constructor).
+        final profileState = ref.read(profileProvider);
+        // Keep showing splash while profile loads.
+        if (profileState.isLoading) {
+          return state.matchedLocation == '/loading' ? null : '/loading';
+        }
+        final profileUser = profileState.valueOrNull;
+        // If profile failed to load, don't block navigation.
+        if (profileUser == null) return isAuthRoute ? '/home' : null;
+
+        final needsOnboarding = !profileUser.hasCompletedOnboarding;
+        if (isAuthRoute) return needsOnboarding ? '/onboarding' : '/home';
+        if (needsOnboarding && !isOnboarding) return '/onboarding';
+        if (!needsOnboarding && isOnboarding) return '/home';
+      }
+
       return null;
     },
     routes: [
@@ -62,6 +93,11 @@ final routerProvider = Provider<GoRouter>((ref) {
         path: '/auth/register',
         builder: (_, __) => const RegisterScreen(),
       ),
+      // Onboarding — full-screen, no bottom nav, shown to new users.
+      GoRoute(
+        path: '/onboarding',
+        builder: (_, __) => const OnboardingScreen(),
+      ),
       // Full-screen recipe detail — shown without the bottom navigation bar.
       GoRoute(
         path: '/recipe-detail',

client/lib/features/profile/profile_screen.dart

@@ -51,12 +51,12 @@ class ProfileScreen extends ConsumerWidget {
 
 // ── Profile body ──────────────────────────────────────────────
 
-class _ProfileBody extends StatelessWidget {
+class _ProfileBody extends ConsumerWidget {
   final User user;
   const _ProfileBody({required this.user});
 
   @override
-  Widget build(BuildContext context) {
+  Widget build(BuildContext context, WidgetRef ref) {
     return ListView(
       padding: const EdgeInsets.fromLTRB(16, 8, 16, 32),
       children: [

client/lib/features/profile/profile_service.dart

@@ -17,6 +17,7 @@ class UpdateProfileRequest {
   final String? activity;
   final String? goal;
   final String? language;
+  final int? dailyCalories;
 
   const UpdateProfileRequest({
     this.name,
@@ -27,6 +28,7 @@ class UpdateProfileRequest {
     this.activity,
     this.goal,
     this.language,
+    this.dailyCalories,
   });
 
   Map<String, dynamic> toJson() {
@@ -39,6 +41,7 @@ class UpdateProfileRequest {
     if (activity != null) map['activity'] = activity;
     if (goal != null) map['goal'] = goal;
     if (language != null) map['preferences'] = {'language': language};
+    if (dailyCalories != null) map['daily_calories'] = dailyCalories;
     return map;
   }
 }

client/lib/shared/models/user.dart

@@ -57,5 +57,6 @@ class User {
   }
 
   bool get hasCompletedOnboarding =>
-      heightCm != null && weightKg != null && dateOfBirth != null && gender != null;
+      heightCm != null && weightKg != null && dateOfBirth != null &&
+      gender != null && goal != null && activity != null;
 }

client/pubspec.lock

@@ -125,10 +125,10 @@ packages:
     dependency: transitive
     description:
       name: characters
-      sha256: f71061c654a3380576a52b451dd5532377954cf9dbd272a78fc8479606670803
+      sha256: faf38497bda5ead2a8c7615f4f7939df04333478bf32e4173fcb06d428b5716b
       url: "https://pub.dev"
     source: hosted
-    version: "1.4.0"
+    version: "1.4.1"
   checked_yaml:
     dependency: transitive
     description:
@@ -668,26 +668,26 @@ packages:
     dependency: transitive
     description:
       name: matcher
-      sha256: dc58c723c3c24bf8d3e2d3ad3f2f9d7bd9cf43ec6feaa64181775e60190153f2
+      sha256: dc0b7dc7651697ea4ff3e69ef44b0407ea32c487a39fff6a4004fa585e901861
       url: "https://pub.dev"
     source: hosted
-    version: "0.12.17"
+    version: "0.12.19"
   material_color_utilities:
     dependency: transitive
     description:
       name: material_color_utilities
-      sha256: f7142bb1154231d7ea5f96bc7bde4bda2a0945d2806bb11670e30b850d56bdec
+      sha256: "9c337007e82b1889149c82ed242ed1cb24a66044e30979c44912381e9be4c48b"
       url: "https://pub.dev"
     source: hosted
-    version: "0.11.1"
+    version: "0.13.0"
   meta:
     dependency: transitive
     description:
       name: meta
-      sha256: e3641ec5d63ebf0d9b41bd43201a66e3fc79a65db5f61fc181f04cd27aab950c
+      sha256: "23f08335362185a5ea2ad3a4e597f1375e78bce8a040df5c600c8d3552ef2394"
       url: "https://pub.dev"
     source: hosted
-    version: "1.16.0"
+    version: "1.17.0"
   mime:
     dependency: transitive
     description:
@@ -993,10 +993,10 @@ packages:
     dependency: transitive
     description:
       name: test_api
-      sha256: "522f00f556e73044315fa4585ec3270f1808a4b186c936e612cab0b565ff1e00"
+      sha256: "8161c84903fd860b26bfdefb7963b3f0b68fee7adea0f59ef805ecca346f0c7a"
       url: "https://pub.dev"
     source: hosted
-    version: "0.7.6"
+    version: "0.7.10"
   typed_data:
     dependency: transitive
     description: