i18n(zh-hant): Align “Clear conversations” wording

Use “清除對話記錄” to align with existing “Clear Conversation → 清除對話”
phrasing for consistency across the UI.

Author: PeterDaveHello

src/_locales/zh-hant/main.json

@@ -95,7 +95,7 @@
   "Pin": "固定側邊",
   "Unpin": "取消固定側邊",
   "Delete Conversation": "刪除對話",
-  "Clear conversations": "清空對話記錄",
+  "Clear conversations": "清除對話記錄",
   "Settings": "設定",
   "Search": "搜尋",
   "Search conversations...": "搜尋對話內容...",