perf: optimize createTask by moving GetCurrentFolder outside loop

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

internal/router/task.go

@@ -28,6 +28,14 @@ func createTask(w http.ResponseWriter, r *http.Request) {
 	}
 	db := util.MustGetDB()
 	defer db.Close()
+
+	// 预先获取下载目录，避免循环中重复查询
+	folder, err := util.GetCurrentFolder(db)
+	if err != nil {
+		util.Res{Success: false, Message: fmt.Sprintf("获取下载目录失败: %v", err)}.Write(w)
+		return
+	}
+
 	for _, item := range body {
 		if !util.CheckBvidFormat(item.Bvid) {
 			util.Res{Success: false, Message: "bvid 格式错误"}.Write(w)
@@ -35,6 +43,7 @@ func createTask(w http.ResponseWriter, r *http.Request) {
 		}
 		if item.Cover == "" || item.Title == "" || item.Owner == "" {
 			util.Res{Success: false, Message: "参数错误"}.Write(w)
+			return
 		}
 
 		if !util.IsValidURL(item.Cover) {
@@ -53,12 +62,8 @@ func createTask(w http.ResponseWriter, r *http.Request) {
 			util.Res{Success: false, Message: "清晰度代码错误"}.Write(w)
 			return
 		}
-		item.Folder, err = util.GetCurrentFolder(db)
+		item.Folder = folder
 		item.Status = "waiting"
-		if err != nil {
-			util.Res{Success: false, Message: fmt.Sprintf("util.GetCurrentFolder: %v.", err)}.Write(w)
-			return
-		}
 		_task := task.Task{TaskInDB: item}
 		_task.Title = util.FilterFileName(_task.Title)
 		err = _task.Create(db)