feat(import): implement recipe import functionality with file and URL support

Co-authored-by: Copilot <copilot@github.com>

flutter/lib/core/router/app_router.dart

@@ -19,6 +19,7 @@ import '../../features/inventory/presentation/consume_inventory_screen.dart';
 import '../../features/inventory/presentation/consumption_history_screen.dart';
 import '../../features/meal_plan/presentation/meal_plan_screen.dart';
 import '../../features/pantry/presentation/pantry_screen.dart';
+import '../../features/import/presentation/import_screen.dart';
 
 final appRouterProvider = Provider<GoRouter>((ref) {
   final authState = ref.watch(authStateProvider);
@@ -66,7 +67,10 @@ final appRouterProvider = Provider<GoRouter>((ref) {
       // /recipes/create must be listed before /recipes/:id to avoid conflict.
       GoRoute(
         path: '/recipes/create',
-        builder: (context, state) => const CreateRecipeScreen(),
+        builder: (context, state) {
+          final initialMarkdown = state.extra as String?;
+          return CreateRecipeScreen(initialMarkdown: initialMarkdown);
+        },
       ),
       GoRoute(
         path: '/recipes/:id',
@@ -168,6 +172,10 @@ final appRouterProvider = Provider<GoRouter>((ref) {
             path: '/baslager',
             builder: (context, state) => const PantryScreen(),
           ),
+          GoRoute(
+            path: '/import',
+            builder: (context, state) => const ImportScreen(),
+          ),
           GoRoute(
             path: '/profile',
             builder: (context, state) => const ProfileScreen(),

flutter/lib/core/ui/app_shell.dart

@@ -39,6 +39,12 @@ class AppShell extends ConsumerWidget {
       icon: Icons.storefront_outlined,
       label: 'Baslager',
     ),
+    _AppDestination(
+      path: '/import',
+      title: 'Importera',
+      icon: Icons.upload_file_outlined,
+      label: 'Importera',
+    ),
     _AppDestination(
       path: '/profile',
       title: 'Profil',