🐛 fix(server): 增加优雅退出与请求超时保护

- 新增 SIGINT/SIGTERM 信号处理与 http.Server.Shutdown,退出前确保统计数据保存、数据库正常关闭
- 为 http.Server 设置 ReadHeaderTimeout/ReadTimeout/WriteTimeout/IdleTimeout,防止慢客户端长期占用连接
- 全局配置指针改为 atomic.Pointer 并提供 GetAppConfig 访问器,消除配置热更新时的数据竞争,同时删除冗余的 manager.config 字段
- 请求统计九组计数器重构为 map[string]*atomic.Int64,统一 incrementStat/getStatsSnapshot 访问,精简约 40 行样板代码
- go mod tidy 清理 go.mod 与 go.sum 中的冗余依赖条目

go.mod

@@ -12,53 +12,25 @@ require (
 
 require (
 	github.com/andybalholm/cascadia v1.3.1 // indirect
-	github.com/bytedance/gopkg v0.1.3 // indirect
-	github.com/bytedance/sonic v1.14.2 // indirect
-	github.com/bytedance/sonic/loader v0.4.0 // indirect
-	github.com/cloudwego/base64x v0.1.6 // indirect
-	github.com/gabriel-vasile/mimetype v1.4.11 // indirect
-	github.com/gin-contrib/sse v1.1.0 // indirect
-	github.com/gin-gonic/gin v1.11.0 // indirect
-	github.com/go-playground/locales v0.14.1 // indirect
-	github.com/go-playground/universal-translator v0.18.1 // indirect
-	github.com/go-playground/validator/v10 v10.28.0 // indirect
-	github.com/goccy/go-json v0.10.5 // indirect
-	github.com/goccy/go-yaml v1.18.0 // indirect
+	github.com/google/go-cmp v0.7.0 // indirect
 	github.com/hashicorp/hcl v1.0.0 // indirect
-	github.com/json-iterator/go v1.1.12 // indirect
-	github.com/klauspost/cpuid/v2 v2.3.0 // indirect
-	github.com/leodido/go-urn v1.4.0 // indirect
 	github.com/magiconair/properties v1.8.7 // indirect
-	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/mitchellh/mapstructure v1.5.0 // indirect
-	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
-	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/pelletier/go-toml/v2 v2.2.4 // indirect
-	github.com/quic-go/qpack v0.5.1 // indirect
-	github.com/quic-go/quic-go v0.55.0 // indirect
 	github.com/sagikazarmark/locafero v0.4.0 // indirect
 	github.com/sagikazarmark/slog-shim v0.1.0 // indirect
 	github.com/sourcegraph/conc v0.3.0 // indirect
 	github.com/spf13/afero v1.11.0 // indirect
 	github.com/spf13/cast v1.6.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
+	github.com/stretchr/testify v1.11.1 // indirect
 	github.com/subosito/gotenv v1.6.0 // indirect
-	github.com/tjfoc/gmsm v1.4.1 // indirect
-	github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
-	github.com/ugorji/go/codec v1.3.1 // indirect
 	go.uber.org/atomic v1.9.0 // indirect
-	go.uber.org/mock v0.6.0 // indirect
 	go.uber.org/multierr v1.9.0 // indirect
-	golang.org/x/arch v0.22.0 // indirect
-	golang.org/x/crypto v0.43.0 // indirect
 	golang.org/x/exp v0.0.0-20230905200255-921286631fa9 // indirect
-	golang.org/x/mod v0.29.0 // indirect
 	golang.org/x/net v0.46.0 // indirect
-	golang.org/x/sync v0.17.0 // indirect
 	golang.org/x/sys v0.37.0 // indirect
 	golang.org/x/text v0.30.0 // indirect
-	golang.org/x/tools v0.38.0 // indirect
-	google.golang.org/protobuf v1.36.10 // indirect
 	gopkg.in/ini.v1 v1.67.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )