feat: Redis Keys 目录树结构浏览 — 按 : 分隔符构建层级树

- buildRedisTree: 将扁平 key 列表按 ':' 分隔构建为树结构
- 文件夹节点可展开/折叠，显示子节点数量
- 叶子节点显示 key type 标签（string/hash/list/set/zset）
- 点击叶子节点自动插入对应查询命令：
  - string → GET key
  - hash → HGETALL key
  - list → LRANGE key 0 -1
  - set → SMEMBERS key
  - zset → ZRANGE key 0 -1 WITHSCORES
- 右侧保留 Key 详情面板（类型/TTL/值预览）
- DB 下拉改为从后端 databases 数据生成
- 树按文件夹优先+字母排序

frontend/src/pages/TicketCreatePage.tsx

@@ -645,6 +645,122 @@ export default function TicketCreatePage() {
   };
 
   /* ---- Redis Tab ---- */
+  /* ---- Redis Tree Node type ---- */
+  interface RedisTreeNode {
+    name: string;
+    fullKey?: string;       // only leaf nodes
+    type?: string;          // key type: string/hash/list/set/zset
+    children?: RedisTreeNode[];
+  }
+
+  /** Build a tree from flat key list using ':' as delimiter */
+  const buildRedisTree = useCallback((keys: RedisKeyItem[]): RedisTreeNode[] => {
+    const root: RedisTreeNode[] = [];
+    for (const k of keys) {
+      const parts = k.key.split(':');
+      let nodes = root;
+      for (let i = 0; i < parts.length; i++) {
+        const part = parts[i];
+        let node = nodes.find(n => n.name === part);
+        if (!node) {
+          node = { name: part, children: [] };
+          nodes.push(node);
+        }
+        if (i === parts.length - 1) {
+          // leaf — replace with leaf node
+          node.fullKey = k.key;
+          node.type = k.type;
+          delete node.children;
+        } else {
+          if (!node.children) node.children = [];
+          nodes = node.children;
+        }
+      }
+    }
+    // sort: folders first, then leaves, alphabetically
+    const sortNodes = (arr: RedisTreeNode[]) => {
+      arr.sort((a, b) => {
+        const aIsLeaf = !!a.fullKey;
+        const bIsLeaf = !!b.fullKey;
+        if (aIsLeaf !== bIsLeaf) return aIsLeaf ? 1 : -1;
+        return a.name.localeCompare(b.name);
+      });
+      arr.forEach(n => { if (n.children) sortNodes(n.children); });
+    };
+    sortNodes(root);
+    return root;
+  }, []);
+
+  /* Redis expanded folders state */
+  const [redisExpanded, setRedisExpanded] = useState<Set<string>>(new Set());
+
+  const toggleRedisFolder = useCallback((path: string) => {
+    setRedisExpanded(prev => {
+      const next = new Set(prev);
+      if (next.has(path)) next.delete(path); else next.add(path);
+      return next;
+    });
+  }, []);
+
+  /** Get Redis command for a key based on its type */
+  const redisCmdForKey = useCallback((key: string, type: string): string => {
+    switch (type) {
+      case 'string': return `GET ${key}`;
+      case 'hash':   return `HGETALL ${key}`;
+      case 'list':   return `LRANGE ${key} 0 -1`;
+      case 'set':    return `SMEMBERS ${key}`;
+      case 'zset':   return `ZRANGE ${key} 0 -1 WITHSCORES`;
+      default:       return `GET ${key}`;
+    }
+  }, []);
+
+  /** Recursive tree renderer */
+  const renderRedisTreeNode = useCallback((node: RedisTreeNode, depth: number, parentPath: string): React.ReactNode => {
+    const path = parentPath ? `${parentPath}:${node.name}` : node.name;
+    const isLeaf = !!node.fullKey;
+    const isExpanded = redisExpanded.has(path);
+
+    if (isLeaf) {
+      return (
+        <button key={path}
+          onClick={() => {
+            const cmd = redisCmdForKey(node.fullKey!, node.type || 'string');
+            setSqlContent(prev => prev + (prev && !prev.endsWith('\n') ? '\n' : '') + cmd);
+            handleSelectRedisKey(node.fullKey!);
+          }}
+          className={`w-full flex items-center gap-1.5 pl-2 pr-2 py-1 text-[11px] font-mono rounded-sm transition-colors group ${
+            selectedRedisKey === node.fullKey ? 'bg-blue-500/10 text-blue-400' : 'hover:bg-[var(--dg-bg-hover)] text-[var(--dg-text-secondary)]'
+          }`}
+          style={{ paddingLeft: `${depth * 14 + 6}px` }}>
+          <KeyRound className="w-3 h-3 text-amber-400 shrink-0" />
+          <span className="truncate flex-1 text-left">{node.name}</span>
+          <span className="text-[9px] px-1 py-0.5 rounded bg-[var(--dg-bg-tertiary)] text-[var(--dg-text-muted)] shrink-0">{node.type}</span>
+          <span className="text-[9px] text-blue-400 opacity-0 group-hover:opacity-100 transition-opacity shrink-0">插入</span>
+        </button>
+      );
+    }
+
+    // folder node
+    const childCount = node.children?.length || 0;
+    return (
+      <div key={path}>
+        <button onClick={() => toggleRedisFolder(path)}
+          className="w-full flex items-center gap-1.5 py-1 text-[11px] font-medium text-[var(--dg-text-secondary)] hover:bg-[var(--dg-bg-hover)] rounded-sm transition-colors"
+          style={{ paddingLeft: `${depth * 14 + 6}px` }}>
+          {isExpanded
+            ? <ChevronDown className="w-3 h-3 text-[var(--dg-text-muted)] shrink-0" />
+            : <ChevronRight className="w-3 h-3 text-[var(--dg-text-muted)] shrink-0" />}
+          <FolderOpen className="w-3 h-3 text-blue-400 shrink-0" />
+          <span className="truncate">{node.name}</span>
+          <span className="text-[9px] text-[var(--dg-text-muted)] ml-auto mr-1">{childCount}</span>
+        </button>
+        {isExpanded && node.children?.map(child => renderRedisTreeNode(child, depth + 1, path))}
+      </div>
+    );
+  }, [redisExpanded, selectedRedisKey, toggleRedisFolder, redisCmdForKey, handleSelectRedisKey]);
+
+  const redisTree = useMemo(() => buildRedisTree(redisKeys), [redisKeys, buildRedisTree]);
+
   const renderRedisTab = () => (
     <div className="p-3 space-y-3">
       {/* Search Bar */}
@@ -654,9 +770,10 @@ export default function TicketCreatePage() {
           onChange={(e) => { setRedisDb(Number(e.target.value)); fetchRedisKeys(); }}
           className="px-2 py-1.5 bg-[var(--dg-bg-primary)] border border-[var(--dg-border)] rounded text-xs focus:outline-none focus:border-blue-500"
         >
-          {Array.from({ length: 16 }, (_, i) => (
+          {databases.length > 0
-            <option key={i} value={i}>DB{i}</option>
+            ? databases.map(db => <option key={db} value={parseInt(db.replace('db', ''))}>{db}</option>)
-          ))}
+            : Array.from({ length: 16 }, (_, i) => <option key={i} value={i}>DB{i}</option>)
+          }
         </select>
         <div className="relative flex-1">
           <Search className="absolute left-2 top-1/2 -translate-y-1/2 w-3 h-3 text-[var(--dg-text-muted)]" />
@@ -665,7 +782,7 @@ export default function TicketCreatePage() {
             onChange={(e) => setRedisPattern(e.target.value)}
             onKeyDown={(e) => e.key === 'Enter' && fetchRedisKeys()}
             className="w-full pl-7 pr-3 py-1.5 bg-[var(--dg-bg-primary)] border border-[var(--dg-border)] rounded text-xs focus:outline-none focus:border-blue-500"
-            placeholder="Key pattern (e.g. user:*)"
+            placeholder="Key pattern (e.g. matcher:*)"
           />
         </div>
         <button
@@ -680,21 +797,9 @@ export default function TicketCreatePage() {
       {/* Key Tree */}
       {redisKeys.length > 0 ? (
         <div className="grid grid-cols-2 gap-2">
-          {/* Key List */}
+          {/* Tree View */}
           <div className="space-y-0.5 max-h-[240px] overflow-y-auto">
-            {redisKeys.map((k) => (
+            {redisTree.map(node => renderRedisTreeNode(node, 0, ''))}
-              <button
-                key={k.key}
-                onClick={() => handleSelectRedisKey(k.key)}
-                className={`flex items-center gap-2 w-full px-2 py-1.5 text-xs rounded transition-colors ${
-                  selectedRedisKey === k.key ? 'bg-blue-500/10 text-blue-400' : 'hover:bg-[var(--dg-bg-hover)]'
-                }`}
-              >
-                <KeyRound className="w-3 h-3 text-[var(--dg-text-muted)]" />
-                <span className="font-mono truncate flex-1 text-left">{k.key}</span>
-                <span className="text-[9px] px-1 py-0.5 rounded bg-[var(--dg-bg-tertiary)] text-[var(--dg-text-muted)]">{k.type}</span>
-              </button>
-            ))}
           </div>
 
           {/* Key Detail */}
@@ -717,7 +822,7 @@ export default function TicketCreatePage() {
                 </pre>
               </div>
             ) : (
-              <div className="text-xs text-[var(--dg-text-muted)] text-center py-4">选择 Key 查看详情</div>
+              <div className="text-xs text-[var(--dg-text-muted)] text-center py-4">点击 Key 查看详情</div>
             )}
           </div>
         </div>