fix: 完善多云同步验证与实例统计

- 修复华为云签名、账单字段与区域映射缓存
- 按真实云实例更新账号服务器数并补充并发测试

backend/controller/cloud_sync.go

@@ -3,6 +3,7 @@ package controller
 import (
 	"net/http"
 	"strconv"
+	"sync"
 	"time"
 
 	"ezops/cloud"
@@ -73,22 +74,60 @@ func (h *CloudSyncHandler) SyncRegions(c *gin.Context) {
 		}
 	}
 
-	// 更新账号的 region_count 和 last_sync_at
-	h.db.Model(&account).Updates(map[string]interface{}{
+	// 并发统计所有可用区域实例数，卡片展示云账号真实资源量。 // Logan.Li
+	serverCount, countedRegions := countCloudInstances(provider, cloudRegions)
+	updates := map[string]interface{}{
 		"region_count": len(cloudRegions),
 		"last_sync_at": time.Now(),
-	})
+	}
+	if countedRegions > 0 {
+		updates["server_count"] = serverCount
+	}
+	// 更新账号区域、实例数量和同步时间。 // Logan.Li
+	h.db.Model(&account).Updates(updates)
 
 	c.JSON(http.StatusOK, model.Response{
 		Code:    200,
 		Message: "同步成功",
 		Data: gin.H{
-			"synced": synced,
-			"total":  len(cloudRegions),
+			"synced":       synced,
+			"total":        len(cloudRegions),
+			"server_count": serverCount,
 		},
 	})
 }
 
+// countCloudInstances 以固定并发统计各区域实例数量，避免串行请求过慢。 // Logan.Li
+func countCloudInstances(provider cloud.Provider, regions []cloud.CloudRegion) (total int, succeeded int) {
+	type countResult struct {
+		count int
+		ok    bool
+	}
+	results := make(chan countResult, len(regions))
+	semaphore := make(chan struct{}, 4)
+	var waitGroup sync.WaitGroup
+	for _, region := range regions {
+		regionID := region.RegionID
+		waitGroup.Add(1)
+		go func() {
+			defer waitGroup.Done()
+			semaphore <- struct{}{}
+			defer func() { <-semaphore }()
+			instances, err := provider.ListInstances(regionID)
+			results <- countResult{count: len(instances), ok: err == nil}
+		}()
+	}
+	waitGroup.Wait()
+	close(results)
+	for result := range results {
+		if result.ok {
+			total += result.count
+			succeeded++
+		}
+	}
+	return total, succeeded
+}
+
 // GetAccountRegions 获取指定云账号的区域列表（按 provider 过滤）
 // GET /cloud-accounts/:id/regions
 func (h *CloudSyncHandler) GetAccountRegions(c *gin.Context) {
@@ -308,11 +347,6 @@ func (h *CloudSyncHandler) ImportInstances(c *gin.Context) {
 		}
 	}
 
-	// 保存该账号当前已关联的资产总数，而不是本次新增数。 // Logan.Li
-	var serverCount int64
-	h.db.Model(&model.Server{}).Where("cloud_account_id = ?", account.ID).Count(&serverCount)
-	h.db.Model(&account).UpdateColumn("server_count", serverCount)
-
 	c.JSON(http.StatusOK, model.Response{
 		Code:    200,
 		Message: "导入完成",