feat: MySQL 索引长度兼容 + 启动自动补列 + 未发布徽标与查询加载态

后端:
- 索引/唯一键改用 mysql_length 前缀索引，适配 MySQL 767 字节限制（error 1071）：knowledge_notes、knowledge_entities、knowledge_graph_blacklist、agent_skills、feedback
- engine.py 新增 _ensure_orm_columns_sync：启动时对比 ORM 元数据，自动 ALTER TABLE 补齐缺失的可空/带默认值列及其索引
- 新增 scripts/audit_index_key_lengths.py 审计全部索引键长度
- 更新 backend/CLAUDE.md 迁移说明

前端:
- 智能体卡片/技能列表：所有者与管理员可见未发布徽标
- 智能体广场：服务端查询进行中时灰显旧结果并悬浮加载提示
- 排行榜入口从 Header 移到欢迎语旁
- threads/hooks.ts：抽取 updateCachedThreadLists 统一处理数组与分页两种缓存形态

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

frontend-web/src/core/threads/hooks.ts

@@ -2,6 +2,7 @@ import type { AIMessage, Message } from "@langchain/langgraph-sdk";
 import type { ThreadsClient } from "@langchain/langgraph-sdk/client";
 import { useStream } from "@langchain/langgraph-sdk/react";
 import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
+import type { QueryClient } from "@tanstack/react-query";
 import { useCallback, useEffect, useRef, useState } from "react";
 import { useNavigate } from "react-router-dom";
 import { toast } from "sonner";
@@ -298,25 +299,19 @@ export function useThreadStream({
       );
       for (const update of updates) {
         if (update && "title" in update && update.title) {
-          void queryClient.setQueriesData(
-            {
-              queryKey: ["threads", "search"],
-              exact: false,
-            },
-            (oldData: Array<AgentThread> | undefined) => {
-              return oldData?.map((t) => {
-                if (t.thread_id === threadIdRef.current) {
-                  return {
+          const nextTitle = update.title;
+          updateCachedThreadLists(queryClient, (threads) =>
+            threads.map((t) =>
+              t.thread_id === threadIdRef.current
+                ? {
                     ...t,
                     values: {
                       ...t.values,
-                      title: update.title,
+                      title: nextTitle,
                     },
-                  };
-                }
-                return t;
-              });
-            },
+                  }
+                : t,
+            ),
           );
         }
       }
@@ -815,6 +810,31 @@ export interface ThreadsPageResult {
   hasMore: boolean;
 }
 
+/**
+ * Apply ``transform`` to the thread array inside every cached
+ * ``["threads", "search"]`` entry. The sidebar queries cache a plain
+ * ``AgentThread[]`` while the paged chats list (`useThreadsPage`) caches a
+ * ``ThreadsPageResult`` object under the same key prefix, so fuzzy
+ * ``setQueriesData`` updaters must handle both shapes.
+ */
+function updateCachedThreadLists(
+  queryClient: QueryClient,
+  transform: (threads: AgentThread[]) => AgentThread[],
+) {
+  queryClient.setQueriesData<AgentThread[] | ThreadsPageResult | undefined>(
+    { queryKey: ["threads", "search"], exact: false },
+    (oldData) => {
+      if (Array.isArray(oldData)) {
+        return transform(oldData);
+      }
+      if (oldData && Array.isArray(oldData.threads)) {
+        return { ...oldData, threads: transform(oldData.threads) };
+      }
+      return oldData;
+    },
+  );
+}
+
 /**
  * Server-side paginated conversation list for the chats page. Unlike
  * `useThreads` (which loads a bounded recent window for the sidebar), this
@@ -935,17 +955,8 @@ export function useDeleteThread() {
       }
     },
     onSuccess(_, { threadId }) {
-      queryClient.setQueriesData(
-        {
-          queryKey: ["threads", "search"],
-          exact: false,
-        },
-        (oldData: Array<AgentThread> | undefined) => {
-          if (oldData == null) {
-            return oldData;
-          }
-          return oldData.filter((t) => t.thread_id !== threadId);
-        },
+      updateCachedThreadLists(queryClient, (threads) =>
+        threads.filter((t) => t.thread_id !== threadId),
       );
     },
     onSettled() {
@@ -1031,27 +1042,18 @@ export function useUpdateThreadMetadata() {
       }
     },
     onSuccess(_, { threadId, metadata }) {
-      queryClient.setQueriesData(
-        {
-          queryKey: ["threads", "search"],
-          exact: false,
-        },
-        (oldData: Array<AgentThread> | undefined) => {
-          if (oldData == null) {
-            return oldData;
-          }
-          return oldData.map((t) =>
-            t.thread_id === threadId
-              ? {
-                  ...t,
-                  metadata: {
-                    ...(t.metadata as Record<string, unknown> | null),
-                    ...metadata,
-                  },
-                }
-              : t,
-          );
-        },
+      updateCachedThreadLists(queryClient, (threads) =>
+        threads.map((t) =>
+          t.thread_id === threadId
+            ? {
+                ...t,
+                metadata: {
+                  ...(t.metadata as Record<string, unknown> | null),
+                  ...metadata,
+                },
+              }
+            : t,
+        ),
       );
     },
   });
@@ -1093,25 +1095,18 @@ export function useRenameThread() {
       });
     },
     onSuccess(_, { threadId, title }) {
-      queryClient.setQueriesData(
-        {
-          queryKey: ["threads", "search"],
-          exact: false,
-        },
-        (oldData: Array<AgentThread>) => {
-          return oldData.map((t) => {
-            if (t.thread_id === threadId) {
-              return {
+      updateCachedThreadLists(queryClient, (threads) =>
+        threads.map((t) =>
+          t.thread_id === threadId
+            ? {
                 ...t,
                 values: {
                   ...t.values,
                   title,
                 },
-              };
-            }
-            return t;
-          });
-        },
+              }
+            : t,
+        ),
       );
     },
   });