feat: Add functionality to move inventory items to pantry and enhance pantry management

- Implemented moveInventoryItemToPantry method in InventoryRepository to facilitate moving items from inventory to pantry.
- Enhanced InventoryScreen with a new header section providing context about the inventory.
- Added a button in SwipeableInventoryTile to move items to pantry with appropriate error handling.
- Introduced movePantryItemToInventory method in PantryRepository to support moving items back to inventory.
- Refactored PantryScreen to rename _addToInventory to _moveToInventory for clarity and updated UI to reflect changes.
- Added AdminPantryItem model to represent pantry items in the admin panel.
- Created AdminPantryPanel for managing pantry items, including moving items to inventory and listing users.
- Developed AdminPrivateProductsPanel for managing private products, allowing promotion to global products.

flutter/lib/features/inventory/presentation/inventory_screen.dart

@@ -95,6 +95,36 @@ class InventoryScreen extends ConsumerWidget {
           ),
         );
 
+        final headerSection = Padding(
+          padding: const EdgeInsets.fromLTRB(12, 12, 12, 4),
+          child: Card(
+            child: Padding(
+              padding: const EdgeInsets.all(16),
+              child: Column(
+                crossAxisAlignment: CrossAxisAlignment.start,
+                children: [
+                  Text(context.l10n.profileInventoryTab, style: Theme.of(context).textTheme.titleMedium),
+                  const SizedBox(height: 8),
+                  Text(
+                    'Din personliga inventarie. Här ser du sådant du faktiskt äger, kan sortera på plats och bäst före, och flytta vidare till recept eller baslager.',
+                    style: Theme.of(context).textTheme.bodyMedium,
+                  ),
+                  const SizedBox(height: 8),
+                  const Wrap(
+                    spacing: 8,
+                    runSpacing: 8,
+                    children: [
+                      Chip(label: Text('User-scope')),
+                      Chip(label: Text('Bäst före')),
+                      Chip(label: Text('Swipa för +/-')),
+                    ],
+                  ),
+                ],
+              ),
+            ),
+          ),
+        );
+
         if (visibleItems.isEmpty) {
           return Stack(
             children: [
@@ -102,6 +132,7 @@ class InventoryScreen extends ConsumerWidget {
                 key: const PageStorageKey<String>('inventory-empty-list'),
                 padding: const EdgeInsets.only(bottom: 88),
                 children: [
+                  headerSection,
                   filterSection,
                   EmptyStateView(title: context.l10n.inventoryEmpty),
                 ],
@@ -124,11 +155,12 @@ class InventoryScreen extends ConsumerWidget {
             ListView.separated(
               key: const PageStorageKey<String>('inventory-main-list'),
               padding: const EdgeInsets.only(bottom: 88),
-              itemCount: visibleItems.length + 1,
+              itemCount: visibleItems.length + 2,
               separatorBuilder: (_, __) => const Divider(height: 1),
               itemBuilder: (context, index) {
                 if (index == 0) return filterSection;
-                final item = visibleItems[index - 1];
+                if (index == 1) return headerSection;
+                final item = visibleItems[index - 2];
                 return SwipeableInventoryTile(item: item);
               },
             ),