perf(frontend): add virtual scrolling to DataTable

Replace direct row rendering with @tanstack/vue-virtual. The table
now only renders visible rows (~20) via padding <tr> placeholders,
eliminating the rendering bottleneck when displaying 100+ rows with
heavy cell components.

Key changes:
- DataTable.vue: integrate useVirtualizer (always-on), virtual row
  template with measureElement for variable row heights, defineExpose
  virtualizer/sortedData for external access, overflow-y/flex CSS
- useSwipeSelect.ts: dual-mode support via optional
  SwipeSelectVirtualContext — data-driven row index lookup and
  selection range when virtualizer is present, original DOM-based
  path preserved for callers that don't pass virtualContext

frontend/pnpm-lock.yaml

@@ -11,6 +11,9 @@ importers:
       '@lobehub/icons':
         specifier: ^4.0.2
         version: 4.0.2(@lobehub/ui@4.9.2)(@types/react@19.2.7)(antd@6.1.3(react-dom@19.2.3(react@19.2.3))(react@19.2.3))(react-dom@19.2.3(react@19.2.3))(react@19.2.3)
+      '@tanstack/vue-virtual':
+        specifier: ^3.13.23
+        version: 3.13.23(vue@3.5.26(typescript@5.6.3))
       '@vueuse/core':
         specifier: ^10.7.0
         version: 10.11.1(vue@3.5.26(typescript@5.6.3))
@@ -1376,6 +1379,14 @@ packages:
     peerDependencies:
       react: '>= 16.3.0'
 
+  '@tanstack/virtual-core@3.13.23':
+    resolution: {integrity: sha512-zSz2Z2HNyLjCplANTDyl3BcdQJc2k1+yyFoKhNRmCr7V7dY8o8q5m8uFTI1/Pg1kL+Hgrz6u3Xo6eFUB7l66cg==}
+
+  '@tanstack/vue-virtual@3.13.23':
+    resolution: {integrity: sha512-b5jPluAR6U3eOq6GWAYSpj3ugnAIZgGR0e6aGAgyRse0Yu6MVQQ0ZWm9SArSXWtageogn6bkVD8D//c4IjW3xQ==}
+    peerDependencies:
+      vue: ^2.7.0 || ^3.0.0
+
   '@types/d3-array@3.2.2':
     resolution: {integrity: sha512-hOLWVbm7uRza0BYXpIIW5pxfrKe0W+D5lrFiAEYR+pb6w3N2SwSMaJbXdUfSEv+dT4MfHBLtn5js0LAWaO6otw==}
 
@@ -5808,6 +5819,13 @@ snapshots:
     dependencies:
       react: 19.2.3
 
+  '@tanstack/virtual-core@3.13.23': {}
+
+  '@tanstack/vue-virtual@3.13.23(vue@3.5.26(typescript@5.6.3))':
+    dependencies:
+      '@tanstack/virtual-core': 3.13.23
+      vue: 3.5.26(typescript@5.6.3)
+
   '@types/d3-array@3.2.2': {}
 
   '@types/d3-axis@3.0.6':