Add ENTRY_VOID movement type and integrate balance entry creation in invoice processing

- Introduced a new movement type 'ENTRY_VOID' to handle invoice reversals, ensuring net balance remains zero.
- Updated the FaLineItem DTOs to replace 'download' with 'discharge' for consistency.
- Implemented balance entry creation in the invoice processing and reverting workflows, enhancing inventory management.
- Adjusted progress tracking messages to reflect the new balance entry generation steps.

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

@@ -166,7 +166,7 @@ class ItemService:
         # FA data uses line.id as primary key
         if line_data.fa_data:
             fa_dict = line_data.fa_data.model_dump(
-                exclude_unset=True, exclude={"line_item_id"}
+                exclude_unset=True, exclude={"line_item_id", "includes_subitems"}
             )
             fa_dict.update(
                 {"id": line.id, "tenant_id": tenant_id, "company_id": company_id}