feat(service): NestJS kernel skeleton + 10-table kernel schema (P1.1+1.2)

Reuses support-service bootstrap/health/prisma patterns. Kernel-only Prisma
schema (scope/source_handle/actor/channel/thread/participant/interaction/
message_part/outbox/processed_event) with orgId/appId NOT NULL and
@@unique([scopeId, idempotencyKey]). Health verified: {status:ok,db:true}.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packages/iios-service/src/app.module.ts

@@ -0,0 +1,9 @@
+import { Module } from '@nestjs/common';
+import { PrismaModule } from './prisma/prisma.module';
+import { HealthController } from './health.controller';
+
+@Module({
+  imports: [PrismaModule],
+  controllers: [HealthController],
+})
+export class AppModule {}