feat: 新增对话数据缓存管理模块，优化统计数据读取性能

src/i18n/locales/en-US/settings.json

@@ -157,6 +157,10 @@
         "name": "Downloads",
         "description": "Screenshots, analysis results, etc."
       },
+      "statsCache": {
+        "name": "Cache Data",
+        "description": "Statistics cache for chat records, auto-rebuilt after clearing"
+      },
       "logs": {
         "name": "Log Files",
         "description": "App logs including import, AI, error logs"

src/i18n/locales/ja-JP/settings.json

@@ -157,6 +157,10 @@
         "name": "ダウンロードディレクトリ",
         "description": "スクリーンショットや分析結果などを含む"
       },
+      "statsCache": {
+        "name": "キャッシュデータ",
+        "description": "チャット記録の統計キャッシュ。クリア後に自動で再構築されます"
+      },
       "logs": {
         "name": "ログファイル",
         "description": "アプリの実行ログ（インポート、AI、エラーなどのログを含む）"

src/i18n/locales/zh-CN/settings.json

@@ -157,6 +157,10 @@
         "name": "下载目录",
         "description": "包含截屏文件、分析结果等"
       },
+      "statsCache": {
+        "name": "缓存数据",
+        "description": "聊天记录的统计缓存，清理后会自动重建"
+      },
       "logs": {
         "name": "日志文件",
         "description": "软件的运行日志，包含导入、AI、错误等日志"

src/i18n/locales/zh-TW/settings.json

@@ -157,6 +157,10 @@
         "name": "下載目錄",
         "description": "包含截圖檔案、分析結果等"
       },
+      "statsCache": {
+        "name": "快取資料",
+        "description": "聊天記錄的統計快取，清理後會自動重建"
+      },
       "logs": {
         "name": "日誌檔案",
         "description": "軟體的執行日誌，包含匯入、AI、錯誤等日誌"

src/pages/settings/components/DataStorage/StorageManageSection.vue

@@ -231,6 +231,7 @@ defineExpose({
               :class="{
                 'bg-green-100 dark:bg-green-900/30': dir.id === 'databases',
                 'bg-violet-100 dark:bg-violet-900/30': dir.id === 'ai',
+                'bg-cyan-100 dark:bg-cyan-900/30': dir.id === 'cache',
                 'bg-amber-100 dark:bg-amber-900/30': dir.id === 'downloads',
                 'bg-blue-100 dark:bg-blue-900/30': dir.id === 'logs',
               }"
@@ -241,6 +242,7 @@ defineExpose({
                 :class="{
                   'text-green-600 dark:text-green-400': dir.id === 'databases',
                   'text-violet-600 dark:text-violet-400': dir.id === 'ai',
+                  'text-cyan-600 dark:text-cyan-400': dir.id === 'cache',
                   'text-amber-600 dark:text-amber-400': dir.id === 'downloads',
                   'text-blue-600 dark:text-blue-400': dir.id === 'logs',
                 }"