fix: 恢复Agent指标并修复时间弹层

- 使用按主键更新避免SQLite字段错误
- 自定义时间选择器改用Portal避免卡片遮挡

backend/controller/agent.go

@@ -127,51 +127,34 @@ func (h *AgentHandler) ReceiveReport(c *gin.Context) {
 	memMB := int64(memGB * 1024)           // GB → MB
 	diskGB := int64(totalDiskGB + 0.5)     // 39.99 → 40
 
-	// 直接 SQL 更新 asset_servers 监控字段
-	// 若 AgentVersion 非空则同步写入，否则保留数据库中已有版本号（防止旧版Agent空字段覆盖已设置的版本）
-	updateSQL := `UPDATE asset_servers SET 
-		cpu_usage = ?, cpu_iowait = ?, memory_usage = ?, disk_usage = ?,
-		cpu = ?, memory = ?, disk = ?,
-		status = ?, agent_status = ?` + func() string {
-		if req.AgentVersion != "" {
-			return `, agent_version = ?`
-		}
-		return ``
-	}()
-	args := []interface{}{
-		req.CPU.UsagePercent, req.CPU.IOWait, req.Memory.UsagePercent, diskAvg,
-		req.CPU.CoreCount, memMB, diskGB,
-		"running", "online",
+	// 使用 map 按主键更新，避免可选系统字段导致原始 SQL 占位参数错位。 // Logan.Li
+	updates := map[string]interface{}{
+		"cpu_usage": req.CPU.UsagePercent, "memory_usage": req.Memory.UsagePercent,
+		"disk_usage": diskAvg,
+		"cpu":        req.CPU.CoreCount, "memory": memMB, "disk": diskGB,
+		"status": "running", "agent_status": "online", "updated_at": time.Now(),
 	}
 	if req.AgentVersion != "" {
-		args = append(args, req.AgentVersion)
+		updates["agent_version"] = req.AgentVersion
 	}
 	if req.System != nil {
 		if req.System.OSVersion != "" {
-			updateSQL += ", os = ?"
-			args = append(args, req.System.OSVersion)
+			updates["os"] = req.System.OSVersion
 		}
 		if req.System.Kernel != "" {
-			updateSQL += ", kernel = ?"
-			args = append(args, req.System.Kernel)
+			updates["kernel"] = req.System.Kernel
 		}
 		if req.System.Uptime > 0 {
-			updateSQL += ", uptime = ?"
-			args = append(args, req.System.Uptime)
+			updates["uptime"] = req.System.Uptime
 		}
 	}
-	updateSQL += ", updated_at = ?"
-	args = append(args, time.Now())
+	var result *gorm.DB
 	if assetMatched {
-		updateSQL += " WHERE id = ?"
-		args = append(args, matchedServer.ID)
+		result = h.db.Model(&model.Server{}).Where("id = ?", matchedServer.ID).Updates(updates)
 	} else {
-		updateSQL += " WHERE hostname = ? OR ip = ?"
-		args = append(args, req.Hostname, matchIP)
+		result = h.db.Model(&model.Server{}).Where("hostname = ? OR ip = ?", req.Hostname, matchIP).Updates(updates)
 	}
 
-	result := h.db.Exec(updateSQL, args...)
-
 	// 如果还是没匹配到 —— 按 hostname 显式查重后再注册 // Logan.Li
 	// asset_servers.hostname 无 UNIQUE 索引，OnConflict 不可靠，故先 First 查重，
 	// 避免 Agent 每次上报（10s）都新建记录导致资产越来越多。