feat(i18n): add saveFailed message and dimensionRatesMixedHint to locale files

- Updated English, Nepali, and Chinese locale files to include a new message for "Failed to save configuration".
- Added a hint for mixed rebate rates within the same dimension to enhance user understanding.
- Improved internationalization support across multiple locales for better user experience in the admin interface.

src/i18n/locales/zh/config.json

@@ -63,7 +63,8 @@
     "refreshing": "刷新中",
     "refresh": "刷新版本",
     "newDraft": "新建草稿",
-    "saveDraft": "保存草稿"
+    "saveDraft": "保存草稿",
+    "saveFailed": "配置保存失败"
   },
   "wallet": {
     "title": "钱包转账限额配置",
@@ -318,6 +319,7 @@
     "deleteFailed": "删除失败",
     "editingVersion": "当前编辑版本 v{{version}} · {{status}}",
     "readOnlyHint": "修改回水前请先创建草稿。",
+    "dimensionRatesMixedHint": "检测到同一维度（2D/3D/4D）内各玩法的首奖级回水比例不完全相同：上方三个百分比输入仅展示按玩法编码排序后的第一个有值示例，实际回水请以下方表格各行数据为准；使用批量输入会先按维度覆盖为同一比例。",
     "fields": {
       "d2": "2D 回水比例 (%)",
       "d3": "3D 回水比例 (%)",