Refactor item management: Update schemas, models, and API routes

- Renamed customs-related schemas in line_items to LineCustomCreate, LineCustomUpdate, and LineCustomResponse.
- Adjusted models to streamline invoice_id mapping in Item model.
- Enhanced item routes to include company_id in summary statistics endpoint.
- Refactored ItemService to improve item creation and update logic, removing redundant methods.
- Updated frontend components for item management, including new item creation and editing functionalities.
- Added API client for items with CRUD operations and improved error handling.

backend/api/v1/modules/a76/items/models.py

@@ -28,8 +28,7 @@ class Item(Base, TenantScopedMixin, TimestampMixin):
     }
 
     id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
-    invoice_id: Mapped[int] = mapped_column(
-        ForeignKey("a76.invoice_header.id"))  # CONSECUTIVO
+    invoice_id: Mapped[int] = mapped_column(ForeignKey("a76.invoice_header.id"))  # CONSECUTIVO
     # Type: IMPORT_TEMP, IMPORT_DEF, EXPORT, REPAIR, etc.
     item_type: Mapped[str] = mapped_column(String(20))
     system_origin: Mapped[str] = mapped_column(String(10))  # SCAF or SCAII