feat: master data endpoint — cached departments, doctors, clinics

Redis-cached (5min TTL) lookups via /api/masterdata/departments,
/api/masterdata/doctors, /api/masterdata/clinics. Warms cache on
startup. Frontend dropdowns use these instead of hardcoded lists.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/masterdata/masterdata.module.ts

@@ -0,0 +1,13 @@
+import { Module } from '@nestjs/common';
+import { PlatformModule } from '../platform/platform.module';
+import { AuthModule } from '../auth/auth.module';
+import { MasterdataController } from './masterdata.controller';
+import { MasterdataService } from './masterdata.service';
+
+@Module({
+    imports: [PlatformModule, AuthModule],
+    controllers: [MasterdataController],
+    providers: [MasterdataService],
+    exports: [MasterdataService],
+})
+export class MasterdataModule {}