feat(#165): Implement BullMQ module setup

Create BullMQ module that shares the existing Valkey connection for job queue processing.

Files Created:
- apps/api/src/bullmq/bullmq.module.ts - Global module configuration
- apps/api/src/bullmq/bullmq.service.ts - Queue management service
- apps/api/src/bullmq/queues.ts - Queue name constants
- apps/api/src/bullmq/index.ts - Barrel exports
- apps/api/src/bullmq/bullmq.service.spec.ts - Unit tests

Files Modified:
- apps/api/src/app.module.ts - Import BullMqModule

Queue Definitions:
- mosaic-jobs (main queue)
- mosaic-jobs-runner (read-only operations)
- mosaic-jobs-weaver (write operations)
- mosaic-jobs-inspector (validation operations)

Implementation:
- Reuses VALKEY_URL from environment (shared connection)
- Follows existing Valkey module patterns
- Includes health check methods
- Proper lifecycle management (init/destroy)
- Queue names use hyphens instead of colons (BullMQ requirement)

Quality Gates:
- Unit tests: 11 passing
- TypeScript: No errors
- ESLint: No violations
- Build: Successful

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/api/src/app.module.ts

@@ -21,6 +21,7 @@ import { BrainModule } from "./brain/brain.module";
 import { CronModule } from "./cron/cron.module";
 import { AgentTasksModule } from "./agent-tasks/agent-tasks.module";
 import { ValkeyModule } from "./valkey/valkey.module";
+import { BullMqModule } from "./bullmq/bullmq.module";
 import { TelemetryModule, TelemetryInterceptor } from "./telemetry";
 
 @Module({
@@ -29,6 +30,7 @@ import { TelemetryModule, TelemetryInterceptor } from "./telemetry";
     PrismaModule,
     DatabaseModule,
     ValkeyModule,
+    BullMqModule,
     AuthModule,
     ActivityModule,
     TasksModule,