refactor(case): Refactor case cost model.

src/dispatch/case/type/service.py

@@ -167,7 +167,7 @@ def update(*, db_session, case_type: CaseType, case_type_in: CaseTypeUpdate) ->
     # Calculate the cost of all non-closed cases associated with this case type
     cases = case_service.get_all_open_by_case_type(db_session=db_session, case_type_id=case_type.id)
     for case in cases:
-        case_cost_service.calculate_case_response_cost(case_id=case.id, db_session=db_session)
+        case_cost_service.calculate_case_response_cost(case=case, db_session=db_session)
 
     if case_type_in.case_template_document:
         case_template_document = document_service.get(

src/dispatch/case_cost/models.py

@@ -1,3 +1,5 @@
+from datetime import datetime
+
 from sqlalchemy import Column, ForeignKey, Integer, Numeric
 from sqlalchemy.ext.associationproxy import association_proxy
 from sqlalchemy.orm import relationship
@@ -40,6 +42,7 @@ class CaseCostUpdate(CaseCostBase):
 class CaseCostRead(CaseCostBase):
     id: PrimaryKey
     case_cost_type: CaseCostTypeRead
+    updated_at: Optional[datetime] = None
 
 
 class CaseCostPagination(Pagination):

src/dispatch/case_cost/scheduled.py

@@ -13,6 +13,7 @@
 
 from .service import (
     calculate_case_response_cost,
+    update_case_response_cost,
     get_or_create_default_case_response_cost,
 )
 
@@ -56,7 +57,8 @@ def calculate_cases_response_cost(db_session: Session, project: Project):
                         continue
 
             # we calculate the response cost amount
-            amount = calculate_case_response_cost(case.id, db_session)
+            update_case_response_cost(case, db_session)
+            amount = calculate_case_response_cost(case, db_session)
             # we don't need to update the cost amount if it hasn't changed
             if case_response_cost.amount == amount:
                 continue