refactor(settings): shorten folder settings labels for better readability

- Rename section title: 'Folder Settings' → 'Default Roots'
- Remove 'Default' prefix from root directory labels:
  - 'Default LoRA Root' → 'LoRA Root'
  - 'Default Checkpoint Root' → 'Checkpoint Root'
  - 'Default Diffusion Model Root' → 'Diffusion Model Root'
  - 'Default Embedding Root' → 'Embedding Root'
- Update translations for all supported languages (en, zh-CN, zh-TW, ja, ko, ru, de, fr, es, he)

locales/zh-CN.json

@@ -259,7 +259,7 @@
             "contentFiltering": "内容过滤",
             "videoSettings": "视频设置",
             "layoutSettings": "布局设置",
-            "folderSettings": "文件夹设置",
+            "folderSettings": "默认根目录",
             "priorityTags": "优先标签",
             "downloadPathTemplates": "下载路径模板",
             "exampleImages": "示例图片",
@@ -355,13 +355,13 @@
             "activeLibraryHelp": "在已配置的库之间切换以更新默认文件夹。更改选择将重新加载页面。",
             "loadingLibraries": "正在加载库...",
             "noLibraries": "尚未配置库",
-            "defaultLoraRoot": "默认 LoRA 根目录",
+            "defaultLoraRoot": "LoRA 根目录",
             "defaultLoraRootHelp": "设置下载、导入和移动时的默认 LoRA 根目录",
-            "defaultCheckpointRoot": "默认 Checkpoint 根目录",
+            "defaultCheckpointRoot": "Checkpoint 根目录",
             "defaultCheckpointRootHelp": "设置下载、导入和移动时的默认 Checkpoint 根目录",
-            "defaultUnetRoot": "默认 Diffusion Model 根目录",
+            "defaultUnetRoot": "Diffusion Model 根目录",
             "defaultUnetRootHelp": "设置下载、导入和移动时的默认 Diffusion Model (UNET) 根目录",
-            "defaultEmbeddingRoot": "默认 Embedding 根目录",
+            "defaultEmbeddingRoot": "Embedding 根目录",
             "defaultEmbeddingRootHelp": "设置下载、导入和移动时的默认 Embedding 根目录",
             "noDefault": "无默认"
         },