feat: 搜索框下滚动、本地服务卡片排序、拖拽末位修复

- 恢复内容区内部滚动：页头/搜索框固定，滚动区域从搜索框下方开始；侧栏跟随内容滚动，侧栏滚轮驱动内容区
- v22：本地服务以 card 行 local-service 参与排序；首页按卡片顺序渲染，后台可拖动排序
- 本地服务卡片后端禁止删除/改名/配置分组
- 修复向下拖动时插到目标之后，倒数第二项可拖到最后
- 验证：搜索框位置固定、侧栏 scrollTop 跟随、本地服务与倒数第二拖末位均落库、首页顺序一致

stash-web/src/components/admin/AdminNext.tsx

@@ -1289,7 +1289,6 @@ function CardsPanel({
 }) {
   const options = useMemo(() => flattenCardsGroups(groups), [groups])
   const [activeId, setActiveId] = useState<number | null>(cards[0]?.id ?? null)
-  const [view, setView] = useState<'local' | 'card'>('local')
   const [pendingId, setPendingId] = useState<number | null>(null)
   const [newOpen, setNewOpen] = useState(false)
   const [newTitle, setNewTitle] = useState('')
@@ -1305,7 +1304,6 @@ function CardsPanel({
       return
     }
     if (pendingId !== null && cards.some((card) => card.id === pendingId)) {
-      setView('card')
       setActiveId(pendingId)
       setPendingId(null)
       return
@@ -1338,12 +1336,16 @@ function CardsPanel({
     setOverId(null)
     if (from === null || from === targetId) return
 
-    const ids = cards.map((card) => card.id)
-    const start = ids.indexOf(from)
-    if (start < 0) return
-    ids.splice(start, 1)
-    const to = ids.indexOf(targetId)
-    ids.splice(to, 0, from)
+    const original = cards.map((card) => card.id)
+    const fromIndex = original.indexOf(from)
+    const targetIndex = original.indexOf(targetId)
+    if (fromIndex < 0 || targetIndex < 0) return
+
+    const ids = original.filter((id) => id !== from)
+    const targetAfter = ids.indexOf(targetId)
+    // 向下拖时插到目标之后，保证能拖到列表最后一项；向上拖时插到目标之前
+    const insertAt = fromIndex < targetIndex ? targetAfter + 1 : targetAfter
+    ids.splice(insertAt, 0, from)
 
     setReordering(true)
     const results = await Promise.all(ids.map((id, index) => updateCard(id, { sort: index })))
@@ -1378,15 +1380,6 @@ function CardsPanel({
           </div>
 
           <div className="cards-side-list">
-            <button
-              type="button"
-              className={`cards-side-item${view === 'local' ? ' is-active' : ''}`}
-              onClick={() => setView('local')}
-            >
-              <span className="cards-side-title">本地服务</span>
-              <span className="cards-side-count">{projects.length}</span>
-            </button>
-
             {cards.map((card) => (
               <button
                 key={card.id}
@@ -1394,16 +1387,13 @@ function CardsPanel({
                 draggable={!reordering}
                 className={[
                   'cards-side-item',
-                  view === 'card' && active?.id === card.id ? 'is-active' : '',
+                  active?.id === card.id ? 'is-active' : '',
                   dragId === card.id ? 'is-dragging' : '',
                   overId === card.id && dragId !== null && dragId !== card.id ? 'is-over' : '',
                 ]
                   .filter(Boolean)
                   .join(' ')}
-                onClick={() => {
-                  setView('card')
-                  setActiveId(card.id)
-                }}
+                onClick={() => setActiveId(card.id)}
                 onDragStart={(event) => {
                   setDragId(card.id)
                   event.dataTransfer.effectAllowed = 'move'
@@ -1426,7 +1416,9 @@ function CardsPanel({
                   ⋮⋮
                 </span>
                 <span className="cards-side-title">{card.title}</span>
-                <span className="cards-side-count">{card.groups.length}</span>
+                <span className="cards-side-count">
+                  {card.key === 'local-service' ? projects.length : card.groups.length}
+                </span>
               </button>
             ))}
             {cards.length === 0 && (
@@ -1444,10 +1436,10 @@ function CardsPanel({
         </aside>
 
         <div className="cards-main">
-          {view === 'local' ? (
-            <LocalServiceTable projects={projects} />
-          ) : active === undefined ? (
+          {active === undefined ? (
             <Text tone="muted">新建一张卡片开始配置。</Text>
+          ) : active.key === 'local-service' ? (
+            <LocalServiceTable projects={projects} />
           ) : (
             <CardTable
               key={active.id}