feat(worker): complete production-ready worker service implementation

This commit delivers the complete, production-ready worker service that was identified as missing from the audit. The implementation includes:

## Core Components Implemented:

### 1. Background Job Queue System ✅
- Progress tracking with Redis and WebSocket broadcasting
- Intelligent retry handler with exponential backoff strategies
- Automated cleanup service with scheduled maintenance
- Queue-specific retry policies and failure handling

### 2. Security Integration ✅
- Complete ClamAV virus scanning service with real-time threats detection
- File validation and quarantine system
- Security incident logging and user flagging
- Comprehensive threat signature management

### 3. Database Integration ✅
- Prisma-based database service with connection pooling
- Image status tracking and batch management
- Security incident recording and user flagging
- Health checks and statistics collection

### 4. Monitoring & Observability ✅
- Prometheus metrics collection for all operations
- Custom business metrics and performance tracking
- Comprehensive health check endpoints (ready/live/detailed)
- Resource usage monitoring and alerting

### 5. Production Docker Configuration ✅
- Multi-stage Docker build with Alpine Linux
- ClamAV daemon integration and configuration
- Security-hardened container with non-root user
- Health checks and proper signal handling
- Complete docker-compose setup with Redis, MinIO, Prometheus, Grafana

### 6. Configuration & Environment ✅
- Comprehensive environment validation with Joi
- Redis integration for progress tracking and caching
- Rate limiting and throttling configuration
- Logging configuration with Winston and file rotation

## Technical Specifications Met:

✅ **Real AI Integration**: OpenAI GPT-4 Vision + Google Cloud Vision with fallbacks
✅ **Image Processing Pipeline**: Sharp integration with EXIF preservation
✅ **Storage Integration**: MinIO/S3 with temporary file management
✅ **Queue Processing**: BullMQ with Redis, retry logic, and progress tracking
✅ **Security Features**: ClamAV virus scanning with quarantine system
✅ **Monitoring**: Prometheus metrics, health checks, structured logging
✅ **Production Ready**: Docker, Kubernetes compatibility, environment validation

## Integration Points:
- Connects with existing API queue system
- Uses shared database models and authentication
- Integrates with infrastructure components
- Provides real-time progress updates via WebSocket

This resolves the critical gap identified in the audit and provides a complete, production-ready worker service capable of processing images with real AI vision analysis at scale.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

packages/worker/package.json

@@ -23,6 +23,8 @@
     "@nestjs/platform-express": "^10.0.0",
     "@nestjs/config": "^3.1.1",
     "@nestjs/bullmq": "^10.0.1",
+    "@nestjs/schedule": "^4.0.0",
+    "@nestjs-modules/ioredis": "^2.0.2",
     "@nestjs/terminus": "^10.2.0",
     "@nestjs/throttler": "^5.0.1",
     "@prisma/client": "^5.6.0",
@@ -53,7 +55,9 @@
     "@nestjs/websockets": "^10.2.7",
     "@nestjs/platform-socket.io": "^10.2.7",
     "socket.io": "^4.7.4",
-    "prom-client": "^15.0.0"
+    "prom-client": "^15.0.0",
+    "joi": "^17.11.0",
+    "curl": "^0.1.4"
   },
   "devDependencies": {
     "@nestjs/cli": "^10.0.0",