refactor: 前后端目录结构模块化 + v2 优化移植与缺陷修复

前端:
- src/srv/api → src/api，按域分文件夹(auth/cluster/host/storage/deployment/collector)
- 新增 http.ts 引擎(http.get/post/put/delete)，域模块改用语义化调用
- index.html 增加 favicon(匹配应用 logo 的 emerald + Activity 脉冲)

后端分层增强(保留包名):
- 新增 repository/：从 models 拆出 JsonDB 持久化层(InitDB/GetDB/Shutdown/RequestSave)
- 新增 dto/：从 controllers 抽出各域请求契约(带 binding 校验)
- 新增 pkg/crypto、pkg/jwt：从 utils 拆出安全原语(外部 jwt 别名 jwtv5 避免冲突)
- models 只留领域实体 + sanitizer；utils 只留 gin/应用相关(response/errors)

v2 优化移植与缺陷修复:
- 移植密钥分离/SSH TOFU/并发写安全/Loki 生产级配置/Docker 加固
- 修复 deployment.go 并发丢更新、Helm values 重复键、EncryptField 哨兵、loki-gateway 端点等审计缺陷
- 实现真正的优雅关停(main.go http.Server + signal + repository.Shutdown)
- 修复登录契约:后端返回 accessToken，前端 auth.ts/Login.tsx 对齐
- 补 crypto/jwt/repository 单元测试(含并发写回归)

验证: go build/vet/test 全绿；npm run build 通过；登录→鉴权→优雅关停冒烟通过

Co-Authored-By: Claude <noreply@anthropic.com>

backend/main.go

@@ -1,10 +1,16 @@
 package main
 
 import (
+	"context"
+	"errors"
 	"log"
+	"net/http"
+	"os/signal"
+	"syscall"
+	"time"
 
 	"lokideploy/config"
-	"lokideploy/models"
+	"lokideploy/repository"
 	"lokideploy/routers"
 	"lokideploy/seed"
 )
@@ -13,7 +19,7 @@ func main() {
 	cfg := config.GetConfig()
 
 	log.Println("Initializing database...")
-	if err := models.InitDB(); err != nil {
+	if err := repository.InitDB(); err != nil {
 		log.Fatalf("Failed to init DB: %v", err)
 	}
 
@@ -21,12 +27,40 @@ func main() {
 	seed.Seed()
 
 	r := routers.SetupRouter()
-
-	log.Printf("LokiDeploy starting on port %s", cfg.ServerPort)
-	log.Printf("API: http://localhost:%s/api/v1", cfg.ServerPort)
-	log.Printf("Default login: admin / admin123")
-
-	if err := r.Run(":" + cfg.ServerPort); err != nil {
-		log.Fatalf("Server failed: %v", err)
+	srv := &http.Server{
+		Addr:         ":" + cfg.ServerPort,
+		Handler:      r,
+		ReadTimeout:  30 * time.Second,
+		WriteTimeout: 30 * time.Second,
+		IdleTimeout:  120 * time.Second,
 	}
+
+	// 监听中断/终止信号，实现优雅关停：先停 HTTP（拒绝新请求、处理完在途请求），
+	// 再 flush 数据库，避免防抖/异步保存丢失最近写入。
+	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
+	defer stop()
+
+	go func() {
+		log.Printf("LokiDeploy starting on port %s", cfg.ServerPort)
+		log.Printf("API: http://localhost:%s/api/v1", cfg.ServerPort)
+		log.Printf("Default login: admin / admin123")
+		if err := srv.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {
+			log.Fatalf("Server failed: %v", err)
+		}
+	}()
+
+	<-ctx.Done()
+	log.Println("Shutdown signal received, draining connections...")
+
+	shutdownCtx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
+	defer cancel()
+	if err := srv.Shutdown(shutdownCtx); err != nil {
+		log.Printf("HTTP shutdown error: %v", err)
+	}
+
+	log.Println("Flushing database...")
+	if err := repository.Shutdown(); err != nil {
+		log.Printf("DB shutdown error: %v", err)
+	}
+	log.Println("LokiDeploy stopped")
 }