feat: 完成数据库迁移系统开发

- 创建完整的迁移框架 (pkg/migration/)
- 版本管理系统，时间戳版本号 (YYYYMMDD_HHMMSS)
- 事务安全的上下迁移机制 (Up/Down)
- 迁移状态跟踪和记录 (migration_records 表)
- 命令行迁移工具 (cmd/migrate/main.go)
- 生产环境迁移脚本 (scripts/production-migrate.sh)
- 生产环境初始化脚本 (scripts/init-production-db.sh)
- 迁移测试脚本 (scripts/test-migration.sh)
- Makefile 集成 (migrate-up, migrate-down, migrate-status)
- 5个预定义迁移 (基础表、默认数据、元数据、收藏、用户资料)
- 自动备份机制、预览模式、详细日志
- 完整文档 (docs/DATABASE_MIGRATION.md)

任务13完成，项目完成率达到42.5%

backend/Makefile

@@ -104,6 +104,74 @@ db-reset:
 	@rm -f ./data/photography.db
 	@echo "Database reset complete. Run 'make quick' to recreate."
 
+# 数据库迁移相关命令
+migrate-status:
+	@echo "Checking migration status..."
+	@go run cmd/migrate/main.go -f $(CONFIG_FILE) -c status
+
+migrate-up:
+	@echo "Running all pending migrations..."
+	@go run cmd/migrate/main.go -f $(CONFIG_FILE) -c up
+
+migrate-down:
+	@echo "Rolling back migrations..."
+	@if [ -z "$(STEPS)" ]; then \
+		echo "Error: Please specify STEPS=n"; \
+		exit 1; \
+	fi
+	@go run cmd/migrate/main.go -f $(CONFIG_FILE) -c down -s $(STEPS)
+
+migrate-reset:
+	@echo "WARNING: This will reset the entire database!"
+	@go run cmd/migrate/main.go -f $(CONFIG_FILE) -c reset
+
+migrate-create:
+	@echo "Creating new migration..."
+	@if [ -z "$(NAME)" ]; then \
+		echo "Error: Please specify NAME=migration_name"; \
+		exit 1; \
+	fi
+	@go run cmd/migrate/main.go -f $(CONFIG_FILE) -c create "$(NAME)"
+
+migrate-version:
+	@echo "Latest migration version:"
+	@go run cmd/migrate/main.go -f $(CONFIG_FILE) -c version
+
+# 数据库初始化（全新安装）
+db-init: setup
+	@echo "Initializing database with migrations..."
+	@go run cmd/migrate/main.go -f $(CONFIG_FILE) -c up
+	@echo "Database initialized successfully!"
+
+# 数据库迁移（生产环境）
+db-migrate:
+	@echo "Running production migrations..."
+	@go run cmd/migrate/main.go -f $(CONFIG_FILE) -c migrate
+
+# 数据库备份
+db-backup:
+	@echo "Creating database backup..."
+	@mkdir -p data/backups
+	@cp data/photography.db data/backups/photography_$$(date +%Y%m%d_%H%M%S).db
+	@echo "Backup created in data/backups/"
+
+# 数据库恢复
+db-restore:
+	@echo "Restoring database from backup..."
+	@if [ -z "$(BACKUP)" ]; then \
+		echo "Error: Please specify BACKUP=filename"; \
+		echo "Available backups:"; \
+		ls -la data/backups/; \
+		exit 1; \
+	fi
+	@if [ -f "data/backups/$(BACKUP)" ]; then \
+		cp "data/backups/$(BACKUP)" data/photography.db; \
+		echo "Database restored from $(BACKUP)"; \
+	else \
+		echo "Error: Backup file not found: $(BACKUP)"; \
+		exit 1; \
+	fi
+
 # 部署准备
 deploy-prep: clean install lint test build
 	@echo "Deployment preparation complete."
@@ -129,6 +197,18 @@ help:
 	@echo "  db-status  - Check database status"
 	@echo "  db-reset   - Reset database"
 	@echo "  deploy-prep - Prepare for deployment"
-	@echo "  help       - Show this help message"
+	@echo ""
+	@echo "Database Migration Commands:"
+	@echo "  migrate-status      - Show migration status"
+	@echo "  migrate-up          - Apply all pending migrations"
+	@echo "  migrate-down STEPS=n - Rollback n migrations"
+	@echo "  migrate-reset       - Reset database (WARNING: destructive)"
+	@echo "  migrate-create NAME=name - Create new migration template"
+	@echo "  migrate-version     - Show latest migration version"
+	@echo "  db-init            - Initialize database with migrations"
+	@echo "  db-migrate         - Run production migrations"
+	@echo "  db-backup          - Create database backup"
+	@echo "  db-restore BACKUP=file - Restore from backup"
+	@echo "  help               - Show this help message"
 
 .PHONY: build run dev quick install gen gen-model clean lint fmt test setup status seed test-seed db-status db-reset deploy-prep help