feat(avatar): 默认头像轮接入（YschTheme sync 件 + 顶栏三态头像）

- src/utils/avatar.ts + src/components/UserAvatar.vue：YschTheme 默认头像轮 sync 下发公共源（取值链 URL > yh-avatar > yh-avatar-sch-default > text）
- layout.vue：顶栏 img 头像换 UserAvatar 三态组件（placement=brand，size=28）；头像/姓名点击统一跳 UserHome 设置页「个人信息」pane（原 /v/userinfo 已下线语义）
- theme.ts/ThemeSwitcher.vue：sync 刷新至 20261006-2013-75c1d10（theme.ts 仅版本戳；ThemeSwitcher 与源仓逐字节一致）
- auto-imports.d.ts：UserAvatar 组件自动登记
当前分支 feat/flow-embed（avatar 轮独立于流程嵌入工作，随分支推送时机一并处理）

src/components/layout.vue

@@ -4,6 +4,7 @@ import { useRoute, useRouter } from "vue-router";
 import { Message } from "view-ui-plus";
 import { resolveMenuPage } from "@/utils/menuRoute";
 import ThemeSwitcher from "@/components/ThemeSwitcher.vue";
+import UserAvatar from "@/components/UserAvatar.vue";
 
 const props = defineProps<{ layoutData: Record<string, any> }>();
 const route = useRoute();
@@ -121,7 +122,8 @@ const linkMenu = (item: any) => {
 };
 
 const linkUserInfo = () => {
-    window.location.href = baseHost.value + "/v/userinfo";
+    // 头像/姓名点击统一跳 UserHome 设置页「个人信息」pane（默认头像轮 2026-09-30，原 /v/userinfo 已下线语义）
+    window.location.href = baseHost.value + "/userhome/front/index.html#/settings?pane=profile";
 };
 const logout = () => {
     let url = window.location.href;
@@ -162,7 +164,7 @@ function linkHomePage() {
             <h4 class="fl align-middle">{{ appName }}</h4>
             <div class="school-bg"></div>
             <div class="header-aside fr">
-                <img :src="userInfo.avatar" v-if="userInfo.avatar" class="fl align-middle" @click="linkUserInfo" />
+                <UserAvatar class="fl align-middle" :src="userInfo.avatar" :name="userInfo.name" :size="28" placement="brand" @click="linkUserInfo" />
                 <a class="name fl align-middle text-ellipsis" href="javascript:void(0);" @click="linkUserInfo">
                     {{ userInfo.name }}
                 </a>