fix(api/settings): wrap batch update in database transaction

Use database transaction for batch settings update to ensure atomicity.
If any individual update fails, the entire batch will be rolled back,
preventing partial configuration updates.

- Wrap all updates in db.Transaction()
- Return detailed error on failure

api/settings/update.go

@@ -8,8 +8,10 @@ package settings
 
 import (
 	"github.com/veypi/vbase/auth"
+	"github.com/veypi/vbase/cfg"
 	"github.com/veypi/vbase/models"
 	"github.com/veypi/vigo"
+	"gorm.io/gorm"
 )
 
 // UpdateItem 更新项
@@ -45,12 +47,28 @@ func update(x *vigo.X, req *UpdateRequest) (*UpdateResponse, error) {
 		return nil, vigo.ErrForbidden.WithString("only admin can update settings")
 	}
 
+	// 使用事务确保批量更新的原子性
+	db := cfg.DB()
 	updated := 0
-	for _, item := range req.Settings {
-		if err := models.SetSetting(item.Key, item.Value, userID); err != nil {
-			return nil, vigo.ErrInternalServer.WithString("failed to update " + item.Key)
+
+	err = db.Transaction(func(tx *gorm.DB) error {
+		for _, item := range req.Settings {
+			var s models.Setting
+			if err := tx.Where("`key` = ?", item.Key).First(&s).Error; err != nil {
+				return err
+			}
+			s.Value = item.Value
+			s.UpdatedBy = userID
+			if err := tx.Save(&s).Error; err != nil {
+				return err
+			}
+			updated++
 		}
-		updated++
+		return nil
+	})
+
+	if err != nil {
+		return nil, vigo.ErrInternalServer.WithError(err)
 	}
 
 	return &UpdateResponse{