perf(desktop): lazy-load renderer routes and pause polling when hidden

Drop the eager Antd global import in favour of unplugin-vue-components
on-demand resolution, async route components, defineAsyncComponent for
the shell/login split, and a dynamic Modal import inside
showClientActionError. Pair that with a visibility-aware runtime poller
that stops the 15s snapshot refresh when the window is hidden and kicks
off an immediate refresh on re-show. Refresh DesktopShell nav with
inline icons and a calmer active/hover treatment, and land
ActionButton/DisclosurePanel/PaginationBar primitives for upcoming
views.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/desktop-client/src/renderer/components/DesktopShell.vue

@@ -1,6 +1,13 @@
 <script setup lang="ts">
 import { computed } from "vue";
 import { RouterLink, RouterView, useRoute } from "vue-router";
+import {
+  AppstoreOutlined,
+  SendOutlined,
+  LinkOutlined,
+  RobotOutlined,
+  ToolOutlined,
+} from "@ant-design/icons-vue";
 
 import { useDesktopRuntime } from "../composables/useDesktopRuntime";
 import { useDesktopSession } from "../composables/useDesktopSession";
@@ -30,30 +37,35 @@ const navItems = computed(() => {
       title: "控制台",
       description: "运行总览、活动流和总体健康度",
       count: data?.summary.issuesOpen ?? 0,
+      icon: AppstoreOutlined,
     },
     {
       to: "/publish-management",
       title: "发布管理",
       description: "查看待发布队列、历史发送结果，并对文章再次发送",
       count: data?.summary.queuedTasks ?? 0,
+      icon: SendOutlined,
     },
     {
       to: "/media-platforms",
       title: "媒体平台",
       description: "发布媒体授权、多个账号绑定与表格化管理",
       count: accounts.filter((item) => publishIDs.has(item.platform)).length,
+      icon: LinkOutlined,
     },
     {
       to: "/ai-platforms",
       title: "AI 平台",
       description: "AI 平台一平台一绑定，按卡片查看状态与归属",
       count: accounts.filter((item) => monitoringIDs.has(item.platform)).length,
+      icon: RobotOutlined,
     },
     {
       to: "/diagnostics",
       title: "诊断",
       description: "vault、scheduler、transport 与原始快照",
       count: data?.clients.length ?? 0,
+      icon: ToolOutlined,
     },
   ];
 });
@@ -90,6 +102,7 @@ const clientLabel = computed(
             @click="handleNavClick(item.to)"
           >
             <div class="nav-copy">
+              <component :is="item.icon" class="nav-icon" />
               <strong>{{ item.title }}</strong>
             </div>
             <span class="nav-count">{{ item.count }}</span>
@@ -207,40 +220,56 @@ h1 {
   display: flex;
   justify-content: space-between;
   align-items: center;
-  padding: 14px 16px;
-  border-radius: 12px;
+  padding: 12px 16px;
+  border-radius: 8px;
   text-decoration: none;
-  background: #ffffff;
-  border: 1px solid #e6edf5;
-  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.02);
+  background: transparent;
+  border: 1px solid transparent;
   transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
 }
 
 .nav-link:hover {
-  border-color: #91caff;
-  box-shadow: 0 4px 12px rgba(22, 119, 255, 0.08);
-  transform: translateY(-1px);
+  background: #f8fafc;
 }
 
 .nav-link.active {
-  background: #f0f7ff;
-  border-color: #1677ff;
-  box-shadow: 0 4px 12px rgba(22, 119, 255, 0.1);
+  background: #e6f4ff;
+  border-color: #e6f4ff;
 }
 
 .nav-copy {
-  display: grid;
-  gap: 4px;
+  display: flex;
+  align-items: center;
+  gap: 12px;
+}
+
+.nav-icon {
+  font-size: 16px;
+  color: #8c8c8c;
+  transition: color 0.2s;
+}
+
+.nav-link:hover .nav-icon {
+  color: #595959;
+}
+
+.nav-link.active .nav-icon {
+  color: #1677ff;
 }
 
 .nav-copy strong {
   font-size: 14px;
-  font-weight: 600;
-  color: #1a1a1a;
+  font-weight: 500;
+  color: #4b5563;
+}
+
+.nav-link:hover .nav-copy strong {
+  color: #1f2937;
 }
 
 .nav-link.active .nav-copy strong {
   color: #1677ff;
+  font-weight: 600;
 }
 
 .nav-count {