style(导航): 隐藏流程总览图页面入口

- App.tsx 移除 /process-roadmap 路由及组件导入
- 首页功能入口卡片移除"流程总览图"
- 侧边栏导航移除"流程总览图"链接
- ProcessDetailPage 移除"返回总览图"按钮及相关逻辑

via [HAPI](https://hapi.run)

Co-Authored-By: HAPI <noreply@hapi.run>

src/App.tsx

@@ -6,7 +6,6 @@ import { ProcessGroupsPage } from './pages/ProcessGroupsPage'
 import { ProcessDetailPage } from './pages/ProcessDetailPage'
 import { ProcessMatrixPage } from './pages/ProcessMatrixPage'
 import { ProcessGraphPage } from './pages/ProcessGraphPage'
-import { ProcessRoadmapPage } from './pages/ProcessRoadmapPage'
 import { ArtifactDetailPage } from './pages/ArtifactDetailPage'
 import { ToolDetailPage } from './pages/ToolDetailPage'
 import { SettingsPage } from './pages/SettingsPage'
@@ -22,7 +21,6 @@ function App() {
         <Route path="/process-groups/:id" element={<ProcessGroupsPage />} />
         <Route path="/process/:id" element={<ProcessDetailPage />} />
         <Route path="/process-matrix" element={<ProcessMatrixPage />} />
-        <Route path="/process-roadmap" element={<ProcessRoadmapPage />} />
         <Route path="/process-graph" element={<ProcessGraphPage />} />
         <Route path="/artifact/:id" element={<ArtifactDetailPage />} />
         <Route path="/tool/:id" element={<ToolDetailPage />} />