fix(workflow): ADR-021 code review fixes (8 bugs)

- fix(transmittal): guard duplicate workflow instance on submit()
- fix(workflow-guard): add organizationId to context so Level-2 RBAC works
- fix(circulation): organizationId context passed relation object not INT FK
- fix(transmittal): require Idempotency-Key header on POST submit endpoint
- fix(workflow): userId non-optional in processTransition controller
- fix(circulation): auto-close counts PENDING and IN_PROGRESS tasks
- fix(transmittal): status badge uses workflowState/DRAFT not purpose field
- fix(workflow): log cache invalidation failures instead of swallowing
- fix(workflow): implement getAvailableActions endpoint stub
- fix(i18n): add removeFile key to EN/TH locales

backend/src/modules/circulation/circulation-workflow.service.ts

@@ -51,7 +51,7 @@ export class CirculationWorkflowService {
       // Context — Circulation เป็น internal document ระดับ Organization (ไม่ผูก contract)
       // Guard Level 2 ตรวจ organizationId; Level 2.5 (contract check) จะ skip เมื่อ contractId = null
       const context: Record<string, unknown> = {
-        organizationId: circulation.organization,
+        organizationId: circulation.organizationId,
         creatorId: userId,
       };