feat(基础设施): 添加运维监控功能的基础配置和依赖

- 更新 .gitignore 排除临时文件
- 添加 ops 监控相关配置项到 config.yaml
- 更新 Go 依赖包（go.mod/go.sum）
- 扩展 config.go 支持 ops 监控配置
- 新增上下文键定义（ClientRequestID）

backend/go.mod

@@ -8,9 +8,11 @@ require (
 	github.com/golang-jwt/jwt/v5 v5.2.2
 	github.com/google/uuid v1.6.0
 	github.com/google/wire v0.7.0
+	github.com/gorilla/websocket v1.5.3
 	github.com/imroc/req/v3 v3.57.0
 	github.com/lib/pq v1.10.9
 	github.com/redis/go-redis/v9 v9.17.2
+	github.com/shirou/gopsutil/v4 v4.25.6
 	github.com/spf13/viper v1.18.2
 	github.com/stretchr/testify v1.11.1
 	github.com/testcontainers/testcontainers-go/modules/postgres v0.40.0
@@ -104,9 +106,9 @@ require (
 	github.com/quic-go/quic-go v0.57.1 // indirect
 	github.com/refraction-networking/utls v1.8.1 // indirect
 	github.com/rivo/uniseg v0.2.0 // indirect
+	github.com/robfig/cron/v3 v3.0.1 // indirect
 	github.com/sagikazarmark/locafero v0.4.0 // indirect
 	github.com/sagikazarmark/slog-shim v0.1.0 // indirect
-	github.com/shirou/gopsutil/v4 v4.25.6 // indirect
 	github.com/sirupsen/logrus v1.9.3 // indirect
 	github.com/sourcegraph/conc v0.3.0 // indirect
 	github.com/spaolacci/murmur3 v1.1.0 // indirect