Add tablet viewport fit for hub one-screen layout.

Hi-DPI tablets like 2560x1600 map to ~1280x800 CSS; broaden fit breakpoints and densify for hub-tablet.

Co-authored-by: Cursor <cursoragent@cursor.com>

manual_trading_hub/static/app.js

@@ -72,8 +72,24 @@
 
   const HUB_PHONE_PRIMARY = { monitor: 1, market: 1, calculator: 1, ai: 1 };
 
+  /** 窄屏布局:仅按视口宽度,监控区/行情等共用 */
+  function isMobileLayout() {
+    return window.matchMedia("(max-width: 720px)").matches;
+  }
+
+  /** 平板 CSS 视口(如 2560×1600 @2x ≈ 1280×800),或高度偏矮的大屏 */
+  function isTabletLayout() {
+    if (isMobileLayout()) return false;
+    const w = window.innerWidth || 0;
+    const h = window.innerHeight || 0;
+    if (w >= 721 && w <= 1599) return true;
+    if (w >= 721 && h > 0 && h <= 920) return true;
+    return false;
+  }
+
   function syncHubPhoneShellClass() {
     document.body.classList.toggle("hub-phone", isMobileLayout());
+    document.body.classList.toggle("hub-tablet", isTabletLayout());
   }
 
   function closeHubMobileMore() {
@@ -1602,11 +1618,6 @@
     return (settingsCache?.exchanges || []).filter((x) => x.enabled);
   }
 
-  /** 窄屏布局:仅按视口宽度,监控区/行情等共用 */
-  function isMobileLayout() {
-    return window.matchMedia("(max-width: 720px)").matches;
-  }
-
   /** AI 教练手机布局:窄屏或手机 PWA(桌面安装的 App 仍走桌面布局) */
   function isMobileAiLayout() {
     if (isMobileLayout()) return true;