Add employee-to-order assignments with FR-EM-3 conflict validation

Adds the Assignment core object (Order x Employee, date range) with full
CRUD, soft-delete/trash integration, and generated API clients.

Layers FR-EM-3 conflict checks onto assignment creation: qualification,
absence/availability, working-hours approximation, cross-order overlap,
and active-contract coverage. Each check's severity (Warning vs. Error)
is configurable at runtime via a new AssignmentValidationSettings
singleton and admin settings panel, instead of being hardcoded - lets
the business tune strictness per check without a redeploy.

Adds a live GET /api/assignments/check endpoint so the create-assignment
dialog can preview conflicts as the user picks employee/dates, before
they hit save, rather than only finding out after submitting.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

omsorgapp/api-client-ts/.openapi-generator/FILES

@@ -5,6 +5,8 @@ package.json
 src/apis/AbsencesApi.ts
 src/apis/AdminEmailApi.ts
 src/apis/AdminSessionsApi.ts
+src/apis/AssignmentValidationSettingsApi.ts
+src/apis/AssignmentsApi.ts
 src/apis/AuditLogApi.ts
 src/apis/AuthApi.ts
 src/apis/ContractsApi.ts
@@ -28,6 +30,10 @@ src/models/AbsenceDecisionRequest.ts
 src/models/AbsenceResponse.ts
 src/models/AbsenceResponsePagedResponse.ts
 src/models/AddUserPermissionOverrideRequest.ts
+src/models/AssignmentConflictResponse.ts
+src/models/AssignmentResponse.ts
+src/models/AssignmentResponsePagedResponse.ts
+src/models/AssignmentValidationSettingsResponse.ts
 src/models/AuditEventCategory.ts
 src/models/AuditLogEntryResponse.ts
 src/models/AuditLogEntryResponsePagedResponse.ts
@@ -35,6 +41,7 @@ src/models/ChangePasswordRequest.ts
 src/models/ContractResponse.ts
 src/models/ContractResponsePagedResponse.ts
 src/models/CreateAbsenceRequest.ts
+src/models/CreateAssignmentRequest.ts
 src/models/CreateContractRequest.ts
 src/models/CreateEmployeeFacilityDistanceRequest.ts
 src/models/CreateEmployeeRequest.ts
@@ -85,6 +92,7 @@ src/models/TimeEntryDecisionRequest.ts
 src/models/TimeEntryResponse.ts
 src/models/TimeEntryResponsePagedResponse.ts
 src/models/TrashAbsenceResponse.ts
+src/models/TrashAssignmentResponse.ts
 src/models/TrashContractResponse.ts
 src/models/TrashEmployeeFacilityDistanceResponse.ts
 src/models/TrashEmployeeResponse.ts
@@ -94,6 +102,8 @@ src/models/TrashFacilityResponse.ts
 src/models/TrashOrderResponse.ts
 src/models/TrashTimeEntryResponse.ts
 src/models/UpdateAbsenceRequest.ts
+src/models/UpdateAssignmentRequest.ts
+src/models/UpdateAssignmentValidationSettingsRequest.ts
 src/models/UpdateContractRequest.ts
 src/models/UpdateDocumentRequest.ts
 src/models/UpdateEmployeeFacilityDistanceRequest.ts