feat: migrate from SQLite to PostgreSQL + Redis architecture

Major database migration to modernize the AI trading system:
• **Database Migration**:
  - Add PostgreSQL 15 and Redis 7 services to docker-compose
  - Create comprehensive PostgreSQL schema with proper indexes and triggers
  - Implement DatabaseInterface for multi-database support
  - Add automatic environment-based database selection
• **Infrastructure**:
  - PostgreSQL: ACID transactions, better concurrency, JSON support
  - Redis: High-performance caching layer (prepared for future use)
  - Docker services with health checks and dependency management
  - Persistent volumes for data safety
• **Code Refactoring**:
  - Abstract database operations through DatabaseInterface
  - Implement PostgreSQL-specific operations with proper syntax
  - Update all SQL queries to support both SQLite and PostgreSQL
  - Fix foreign key constraints and data type conversions
• **Migration Tools**:
  - Automated data migration script from SQLite to PostgreSQL
  - Complete backup and restore procedures
  - One-click migration script with validation
• **Compatibility**:
  - Backward compatible with existing SQLite deployments
  - Environment variable driven database selection
  - Preserved all existing functionality and data
🎯 Benefits: Better performance, scalability, and reliability for production deployments

docker-compose.yml

@@ -1,4 +1,44 @@
 services:
+  # PostgreSQL Database
+  postgres:
+    image: postgres:15-alpine
+    container_name: nofx-postgres
+    restart: unless-stopped
+    environment:
+      POSTGRES_DB: ${POSTGRES_DB:-nofx}
+      POSTGRES_USER: ${POSTGRES_USER:-nofx}
+      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:-nofx123456}
+    volumes:
+      - postgres_data:/var/lib/postgresql/data
+      - ./db/init.sql:/docker-entrypoint-initdb.d/init.sql:ro
+    ports:
+      - "${POSTGRES_PORT:-5433}:5432"
+    networks:
+      - nofx-network
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U ${POSTGRES_USER:-nofx}"]
+      interval: 10s
+      timeout: 5s
+      retries: 5
+
+  # Redis Cache
+  redis:
+    image: redis:7-alpine
+    container_name: nofx-redis
+    restart: unless-stopped
+    command: redis-server --appendonly yes --requirepass ${REDIS_PASSWORD:-redis123456}
+    volumes:
+      - redis_data:/data
+    ports:
+      - "${REDIS_PORT:-6380}:6379"
+    networks:
+      - nofx-network
+    healthcheck:
+      test: ["CMD", "redis-cli", "--raw", "incr", "ping"]
+      interval: 10s
+      timeout: 3s
+      retries: 5
+
   # Backend service (API and core logic)
   nofx:
     build:
@@ -10,13 +50,25 @@ services:
       - "${NOFX_BACKEND_PORT:-8080}:8080"
     volumes:
       - ./config.json:/app/config.json:ro
-      - ./config.db:/app/config.db
       - ./beta_codes.txt:/app/beta_codes.txt:ro
       - ./decision_logs:/app/decision_logs
       - ./prompts:/app/prompts
       - /etc/localtime:/etc/localtime:ro  # Sync host time
     environment:
       - TZ=${NOFX_TIMEZONE:-Asia/Shanghai}  # Set timezone
+      - POSTGRES_HOST=postgres
+      - POSTGRES_PORT=5432
+      - POSTGRES_DB=${POSTGRES_DB:-nofx}
+      - POSTGRES_USER=${POSTGRES_USER:-nofx}
+      - POSTGRES_PASSWORD=${POSTGRES_PASSWORD:-nofx123456}
+      - REDIS_HOST=redis
+      - REDIS_PORT=6379
+      - REDIS_PASSWORD=${REDIS_PASSWORD:-redis123456}
+    depends_on:
+      postgres:
+        condition: service_healthy
+      redis:
+        condition: service_healthy
     networks:
       - nofx-network
     healthcheck:
@@ -48,4 +100,8 @@ services:
 
 networks:
   nofx-network:
-    driver: bridge
+    driver: bridge
+
+volumes:
+  postgres_data:
+  redis_data: