feat: add Skill route and navigation

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/src/components/SidebarNav.vue

@@ -10,11 +10,12 @@ const auth = useAuthStore()
 const navItems = [
   { name: '沟通系统', path: '/chat', icon: MessageCircle },
   { name: '智能链路', path: '/agents', icon: Bot },
+  { name: 'Skill 市场', path: '/skills', icon: Bot },
   { name: '资料中枢', path: '/knowledge', icon: BookOpen },
-  { name: '关系图谱', path: '/graph', icon: Network },
+  { name: '知识大脑', path: '/graph', icon: Network },
   { name: '任务矩阵', path: '/kanban', icon: LayoutGrid },
-  { name: '事务栈', path: '/todo', icon: CheckSquare },
-  { name: '交互广场', path: '/forum', icon: MessageSquare },
+  { name: '任务调度', path: '/todo', icon: CheckSquare },
+  { name: '信息交易所', path: '/forum', icon: MessageSquare },
   { name: '数据舱', path: '/stats', icon: Activity },
   { name: '系统设置', path: '/settings', icon: Settings },
 ]