feat: 公开用户排行榜页面 + 修复 checkpointer 连接与前端依赖

- 新增公开排行榜页面与后端 public_leaderboard 路由
- 完善 skills/agents 路由
- checkpointer Postgres 改用连接池(自愈), 解决连接关闭后定时任务连环失败
- 修复前端 mermaid 依赖未声明导致 Vite 解析失败 (新增 pnpm-lock)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

frontend-web/src/components/workspace/settings/skill-settings-page.tsx

@@ -22,6 +22,7 @@ import {
   Trash2Icon,
   TrendingUpIcon,
   Upload,
+  UserIcon,
 } from "lucide-react";
 import { useRouter } from "next/navigation";
 import { useCallback, useEffect, useMemo, useRef, useState } from "react";
@@ -631,6 +632,12 @@ export function SkillRow({
 
   const metaNodes = (
     <>
+      {!isBuiltin && skill.owner_username && (
+        <div className="text-muted-foreground mt-1 flex items-center gap-1 text-xs">
+          <UserIcon className="size-3" />
+          发布者：{desensitize(skill.owner_username)}
+        </div>
+      )}
       {skill.use_count !== undefined && (
         <div className="text-muted-foreground mt-1 text-xs">
           {skill.use_count > 0
@@ -649,15 +656,15 @@ export function SkillRow({
 
   const actionButtons = (
     <>
-      <Button
-        size="icon"
-        variant="ghost"
-        className="h-8 w-8 shrink-0"
-        onClick={() => setTagPickerOpen(true)}
-        title={t.adminTags.manageTags}
-      >
-        <TagsIcon className="size-3.5" />
-      </Button>
+      <Button
+        size="icon"
+        variant="ghost"
+        className="h-8 w-8 shrink-0"
+        onClick={() => setTagPickerOpen(true)}
+        title={t.adminTags.manageTags}
+      >
+        <TagsIcon className="size-3.5" />
+      </Button>
       {canManage && (
         <Button
           size="icon"
@@ -842,13 +849,13 @@ export function SkillRow({
           </DialogFooter>
         </DialogContent>
       </Dialog>
-      <TagPickerDialog
-        open={tagPickerOpen}
-        onOpenChange={setTagPickerOpen}
-        targetType="skill"
-        targetId={skill.name}
-        currentTags={skill.tags ?? []}
-      />
+      <TagPickerDialog
+        open={tagPickerOpen}
+        onOpenChange={setTagPickerOpen}
+        targetType="skill"
+        targetId={skill.name}
+        currentTags={skill.tags ?? []}
+      />
       <SkillDetailDialog
         skillName={skill.name}
         open={detailOpen}