Remove WorkflowPage and associated references from AppShell and Sidebar components

frontend/src/components/layout/AppShell.tsx

@@ -12,7 +12,6 @@ import { ComponentsToolsPage } from "@/components/pages/ComponentsToolsPage";
 import { HistoryPage } from "@/components/pages/HistoryPage";
 import { DashboardPage } from "@/components/pages/DashboardPage";
 import { TestPage } from "@/components/pages/TestPage";
-import { WorkflowPage } from "@/components/pages/WorkflowPage";
 import { ProfilePage } from "@/components/pages/ProfilePage";
 
 export type NavKey =
@@ -24,7 +23,6 @@ export type NavKey =
   | "history"
   | "dashboard"
   | "test"
-  | "workflow"
   | "profile";
 
 
@@ -53,7 +51,6 @@ export function AppShell() {
           {active === "history" && <HistoryPage />}
           {active === "dashboard" && <DashboardPage />}
           {active === "test" && <TestPage />}
-          {active === "workflow" && <WorkflowPage />}
           {active === "profile" && <ProfilePage />}
         </div>
       </main>

frontend/src/components/layout/Sidebar.tsx

@@ -12,7 +12,6 @@ import {
   Home,
   PlayCircle,
   Video,
-  Workflow,
 } from "lucide-react";
 import type { NavKey } from "./AppShell";
 

frontend/src/components/pages/WorkflowPage.tsx

@@ -1,10 +0,0 @@
-import { PlaceholderPage } from "./PlaceholderPage";
-
-export function WorkflowPage() {
-  return (
-    <PlaceholderPage
-      title="工作流"
-      description="管理与编排可复用的助手工作流，支持多轮任务与工具调用。"
-    />
-  );
-}