[STYLE] 優化機台設定頁面載入提示與 AJAX 互動體驗

1. 新增全站頂部進度條觸發機制，在搜尋或分頁時提供視覺反饋。
2. 為機台設定頁面新增奢華風 Spinner 載入遮罩，替代原本抖動的骨架屏。
3. 優化分頁與搜尋的 AJAX 回傳邏輯，載入時降低背景透明度以維持版面穩定。
4. 新增多語系翻譯字串：Failed to load tab content。

lang/en.json

@@ -1153,5 +1153,6 @@
     "Waiting": "Waiting",
     "Publish Time": "Publish Time",
     "Expired Time": "Expired Time",
-    "Inventory synced with machine": "Inventory synced with machine"
+    "Inventory synced with machine": "Inventory synced with machine",
+    "Failed to load tab content": "Failed to load tab content"
 }

lang/ja.json

@@ -1152,5 +1152,6 @@
     "Waiting": "待機中",
     "Publish Time": "公開時間",
     "Expired Time": "終了時間",
-    "Inventory synced with machine": "在庫が機体と同期されました"
+    "Inventory synced with machine": "在庫が機体と同期されました",
+    "Failed to load tab content": "タブコンテンツの読み込みに失敗しました"
 }

lang/zh_TW.json

@@ -1158,5 +1158,6 @@
     "Waiting": "等待中",
     "Publish Time": "發布時間",
     "Expired Time": "下架時間",
-    "Inventory synced with machine": "庫存已與機台同步"
+    "Inventory synced with machine": "庫存已與機台同步",
+    "Failed to load tab content": "載入分頁內容失敗"
 }