feat: Add inventory management feature with CRUD operations

- Implemented inventory screen to display items with details.
- Added create, edit, and consume inventory screens for managing items.
- Introduced consumption history screen to track item usage.
- Created inventory repository and providers for API interactions.
- Enhanced routing to include inventory-related paths.
- Added necessary models for inventory items and consumption history.
- Integrated error handling and loading states for better user experience.

flutter/lib/features/inventory/domain/inventory_consumption.dart

@@ -0,0 +1,29 @@
+class InventoryConsumption {
+  final int id;
+  final int inventoryItemId;
+  final double amountUsed;
+  final String unit;
+  final String? comment;
+  final DateTime createdAt;
+
+  const InventoryConsumption({
+    required this.id,
+    required this.inventoryItemId,
+    required this.amountUsed,
+    required this.unit,
+    this.comment,
+    required this.createdAt,
+  });
+
+  factory InventoryConsumption.fromJson(Map<String, dynamic> json) {
+    final itemMap = json['inventoryItem'] as Map<String, dynamic>?;
+    return InventoryConsumption(
+      id: json['id'] as int,
+      inventoryItemId: json['inventoryItemId'] as int,
+      amountUsed: double.tryParse(json['amountUsed']?.toString() ?? '0') ?? 0,
+      unit: itemMap?['unit'] as String? ?? '',
+      comment: json['comment'] as String?,
+      createdAt: DateTime.tryParse(json['createdAt']?.toString() ?? '') ?? DateTime.now(),
+    );
+  }
+}

flutter/lib/features/inventory/domain/inventory_item.dart

@@ -0,0 +1,43 @@
+class InventoryItem {
+  final int id;
+  final int productId;
+  final String productName;
+  final double quantity;
+  final String unit;
+  final String? location;
+  final String? brand;
+  final String? purchaseDate;
+  final String? bestBeforeDate;
+  final bool opened;
+  final String? comment;
+
+  const InventoryItem({
+    required this.id,
+    required this.productId,
+    required this.productName,
+    required this.quantity,
+    required this.unit,
+    this.location,
+    this.brand,
+    this.purchaseDate,
+    this.bestBeforeDate,
+    required this.opened,
+    this.comment,
+  });
+
+  factory InventoryItem.fromJson(Map<String, dynamic> json) {
+    return InventoryItem(
+      id: json['id'] as int,
+      productId: json['productId'] as int,
+      productName: (json['product'] as Map<String, dynamic>?)?['name'] as String? ?? '',
+      quantity: double.tryParse(json['quantity']?.toString() ?? '0') ?? 0,
+      unit: json['unit'] as String? ?? '',
+      location: json['location'] as String?,
+      brand: json['brand'] as String?,
+      purchaseDate: json['purchaseDate'] as String?,
+      bestBeforeDate: json['bestBeforeDate'] as String?,
+      opened: json['opened'] as bool? ?? false,
+      comment: json['comment'] as String?,
+    );
+  }
+}