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/admin/domain/admin_pantry_item.dart

@@ -0,0 +1,42 @@
+class AdminPantryItem {
+  final int id;
+  final int userId;
+  final String username;
+  final String userEmail;
+  final int productId;
+  final String productName;
+  final String? productCanonicalName;
+  final String? location;
+
+  const AdminPantryItem({
+    required this.id,
+    required this.userId,
+    required this.username,
+    required this.userEmail,
+    required this.productId,
+    required this.productName,
+    this.productCanonicalName,
+    this.location,
+  });
+
+  String get displayName {
+    final canonical = productCanonicalName?.trim();
+    if (canonical != null && canonical.isNotEmpty) return canonical;
+    return productName;
+  }
+
+  factory AdminPantryItem.fromJson(Map<String, dynamic> json) {
+    final user = (json['user'] as Map<String, dynamic>?) ?? const {};
+    final product = (json['product'] as Map<String, dynamic>?) ?? const {};
+    return AdminPantryItem(
+      id: (json['id'] as num).toInt(),
+      userId: (json['userId'] as num).toInt(),
+      username: user['username'] as String? ?? '',
+      userEmail: user['email'] as String? ?? '',
+      productId: (json['productId'] as num).toInt(),
+      productName: product['name'] as String? ?? '',
+      productCanonicalName: product['canonicalName'] as String?,
+      location: json['location'] as String?,
+    );
+  }
+}