完善浏览器配置库与未保存提示

- 新增 IndexedDB 配置保存、加载、删除及批量导入导出

- 配置列表支持选中、双击加载和悬浮操作提示

- 新增未保存提示设置，默认关闭并持久化到浏览器

- 优化配置管理界面并同步九种语言文案

- 更新开发文档与生产构建产物

src/i18n/locales/en.json

@@ -87,12 +87,13 @@
     "tickWidth": "Tick line width",
     "axisColor": "Axis color",
     "showAxisLabels": "Show tick values",
+    "unsavedPrompt": "Prompt for unsaved changes",
     "cacheNote": "Settings are saved automatically in this browser"
   },
   "config": {
     "title": "Configuration",
     "save": "Save Config",
-    "saveTitle": "Save the complete editor configuration (Ctrl+S)",
+    "saveTitle": "Save configuration to browser cache",
     "load": "Load Config",
     "loadTitle": "Load an editor configuration file",
     "presets": "Preset list",
@@ -110,7 +111,35 @@
     "presetRestoring": "Parsing and restoring preset resources…",
     "presetComplete": "Preset loaded",
     "presetListError": "Unable to read preset list",
-    "presetReadError": "Unable to read preset: {file}"
+    "presetReadError": "Unable to read preset: {file}",
+    "local": {
+      "listTitle": "Configuration List",
+      "empty": "No configurations saved in this browser",
+      "saveTitle": "Save configuration to browser cache",
+      "name": "Configuration name",
+      "namePlaceholder": "For example: Firework effect",
+      "load": "Load",
+      "loadHint": "Double-click to load",
+      "download": "Download",
+      "delete": "Delete",
+      "downloadCurrent": "Download Current Configuration",
+      "downloadAll": "Download All Configurations",
+      "loadAll": "Load All Configurations",
+      "loadAllConfirm": "Import {count} configuration files? Existing configurations with the same names will be overwritten.",
+      "loadAllDone": "Loaded {count} configurations from files",
+      "loadAllPartial": "Imported {imported} configurations; {failed} files failed",
+      "overwriteSave": "“{name}” already exists. Overwrite it?",
+      "loadOverwrite": "Loading “{name}” will replace the current scene and discard unsaved changes. Continue?",
+      "deleteConfirm": "Delete “{name}”?",
+      "nameRequired": "Enter a configuration name",
+      "nameInvalid": "The name cannot contain \\ / : * ? \" ＜ ＞ |",
+      "storageUnavailable": "Browser local storage is unavailable",
+      "saved": "Saved to browser: {name}",
+      "loaded": "Loaded from browser: {name}",
+      "deleted": "Deleted browser configuration: {name}",
+      "downloadEmpty": "No configurations to download",
+      "downloaded": "Downloaded: {name}"
+    }
   },
   "curve": {
     "bezierHint": "Drag square handles · Double-click empty space to add · Double-click a node to delete",