feat(audit): F1+F2 告警静默规则标记完成 + 审计日志CSV导出实现

F1 告警静默规则 [done]:
- 后端 alert_silence.go: CRUD + Toggle (onetime/daily/weekly 三模式)
- 告警引擎 isSilenced 集成 (alert_engine.go)
- 前端 SilenceRuleTab + SilenceDialog
- 路由 /alerts/silences 已注册

F2 审计日志导出 [done]:
- 重写 ExportAuditLogs: 真正的 CSV 导出 (encoding/csv + UTF-8 BOM)
- 支持 module/action/username/startTime/endTime 筛选
- 导出限制 10000 条防溢出，自动记录审计日志
- JSON 格式向后兼容 (format=json)
- 前端 exportLogs 传递查询参数

同时包含累积的前期工作:
- 目录重构 internal/ -> controller/model/router (v0.55-v0.57)
- 后端分层架构 dto/repository/service/utils
- 审计模块全功能 (终端审计/操作审计/登录日志)
- asciicast v2 录制格式
- SFTP 文件浏览器
- StatStrip 紧凑统计条
- 在线会话自动刷新
- LiveMonitor WebSocket 诊断修复

验证: go build ✅ | npm run build ✅ | Docker 部署 ✅ | 10 回归端点 ✅ | CSV 导出 ✅ | 静默 CRUD ✅

backend/config.yaml.example

@@ -1,161 +1,38 @@
 # AIOps 配置文件示例
-# 复制此文件为 config.yaml 并根据实际情况修改
+# 复制为 config.yaml 并根据实际环境修改
+# 代码只读取下方列出的字段（见 backend/config/config.go）
 
-# 应用配置
-app:
-  name: "AIOps"
-  version: "1.0.0"
-  port: 8080
-  mode: "debug"  # debug, release, test
+# 运行模式: debug | release
+mode: "release"
+port: "8080"
+log_level: "info"
 
-# 数据库配置
+# MySQL 数据库
 database:
-  # 数据库类型: mysql, postgres
   driver: "mysql"
-  # MySQL配置
-  mysql:
-    host: "localhost"
-    port: 3306
-    username: "ezops"
-    password: "your_password"
-    database: "ezops"
-    charset: "utf8mb4"
-    max_idle_conns: 10
-    max_open_conns: 100
-    conn_max_lifetime: 3600  # 秒
-  # PostgreSQL配置
-  postgres:
-    host: "localhost"
-    port: 5432
-    username: "ezops"
-    password: "your_password"
-    database: "ezops"
-    ssl_mode: "disable"
-    max_idle_conns: 10
-    max_open_conns: 100
-    conn_max_lifetime: 3600  # 秒
+  host: "mysql"                  # Docker Compose 用服务名，外部连接用 IP
+  port: 3306
+  user: "aiops"
+  password: "CHANGE_ME"
+  dbname: "aiops"
+  charset: "utf8mb4"
+  max_conn: 100
+  max_idle: 10
 
-# Redis配置
+# Redis 缓存 (可选，driver=redka 为内嵌模式无需外部 Redis)
 redis:
-  enabled: false
-  host: "localhost"
+  driver: "redis"               # redka (内嵌) | redis (外部)
+  host: "redis"
   port: 6379
   password: ""
-  database: 0
-  pool_size: 10
+  db: 0
 
-# JWT配置
+# JWT 认证
 jwt:
-  secret: "your_jwt_secret_key_change_this_in_production"
-  expire_hours: 24
-  refresh_hours: 168  # 7天
+  secret: "CHANGE_ME_JWT_SECRET"
+  expire_hour: 24
 
-# 日志配置
-log:
-  level: "info"  # debug, info, warn, error
-  format: "json"  # json, console
-  output: "stdout"  # stdout, file
-  file_path: "./logs/ezops.log"
-  max_size: 100  # MB
-  max_backups: 10
-  max_age: 30  # 天
-  compress: true
-
-# CORS配置
-cors:
-  allowed_origins:
-    - "http://localhost:3000"
-    - "http://localhost:5173"
-  allowed_methods:
-    - "GET"
-    - "POST"
-    - "PUT"
-    - "DELETE"
-    - "OPTIONS"
-  allowed_headers:
-    - "*"
-  allow_credentials: true
-  max_age: 86400
-
-# 文件上传配置
-upload:
-  max_size: 10485760  # 10MB
-  allowed_types:
-    - ".xlsx"
-    - ".xls"
-    - ".csv"
-    - ".json"
-    - ".yaml"
-    - ".yml"
-  upload_path: "./uploads"
-
-# WebSocket配置
+# WebSocket (kubectl 终端)
 websocket:
   read_buffer_size: 1024
   write_buffer_size: 1024
-  ping_period: 30  # 秒
-  pong_wait: 60    # 秒
-
-# 监控配置
-monitor:
-  enabled: true
-  metrics_port: 9090
-  pprof_enabled: false
-
-# 云平台配置
-cloud:
-  # 阿里云配置
-  aliyun:
-    enabled: false
-    access_key_id: ""
-    access_key_secret: ""
-    region: "cn-hangzhou"
-  # 腾讯云配置
-  tencent:
-    enabled: false
-    secret_id: ""
-    secret_key: ""
-    region: "ap-guangzhou"
-  # AWS配置
-  aws:
-    enabled: false
-    access_key_id: ""
-    secret_access_key: ""
-    region: "us-east-1"
-  # 华为云配置
-  huawei:
-    enabled: false
-    access_key_id: ""
-    secret_access_key: ""
-    region: "cn-north-1"
-
-# 告警通知配置
-notification:
-  # 邮件配置
-  email:
-    enabled: false
-    smtp_host: "smtp.example.com"
-    smtp_port: 587
-    username: ""
-    password: ""
-    from: "ezops@example.com"
-    use_tls: true
-  # 钉钉配置
-  dingtalk:
-    enabled: false
-    webhook_url: ""
-    secret: ""
-  # 企业微信配置
-  wechat:
-    enabled: false
-    webhook_url: ""
-  # Slack配置
-  slack:
-    enabled: false
-    webhook_url: ""
-
-# 审计日志配置
-audit:
-  enabled: true
-  retention_days: 365  # 日志保留天数
-  async_write: true    # 异步写入