feat(imitation): add article imitation create flow

Introduce 仿写创作: new list and create views, backend imitation service
and prompt templates, worker task routing for imitation jobs, and one-click
rewrite triggers from question citation sources. Surface source article
URL/title on article list/detail, and restrict failed articles to delete-only.

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

apps/admin-web/src/layouts/AppShell.vue

@@ -11,7 +11,7 @@ import {
   TranslationOutlined,
 } from "@ant-design/icons-vue";
 import { useQuery } from "@tanstack/vue-query";
-import { computed } from "vue";
+import { computed, type Component } from "vue";
 import { useRoute, useRouter } from "vue-router";
 import { useI18n } from "vue-i18n";
 
@@ -39,6 +39,23 @@ const selectedKeys = computed(() => {
 });
 const pageTitle = computed(() => t(String(route.meta.titleKey ?? "route.workspace.title")));
 
+type HeaderBreadcrumb = {
+  label: string;
+  path?: string;
+};
+
+type NavItem = {
+  key: string;
+  label: string;
+  icon?: Component;
+};
+
+type NavSection = {
+  key: string;
+  title: string;
+  items: NavItem[];
+};
+
 const localeOptions = computed(() => [
   { label: t("locale.zh-CN"), value: "zh-CN" },
   { label: t("locale.en-US"), value: "en-US" },
@@ -55,7 +72,7 @@ const currentLocaleLabel = computed(() => {
   return localeOptions.value.find((opt) => opt.value === currentLocale.value)?.label ?? "Language";
 });
 
-const navSections = computed(() => {
+const navSections = computed<NavSection[]>(() => {
   const base = [
     {
       key: "workspace",
@@ -75,7 +92,7 @@ const navSections = computed(() => {
         { key: "/articles/templates", label: t("nav.templates") },
         { key: "/articles/custom", label: t("nav.custom") },
         { key: "/articles/free-create", label: t("nav.freeCreate") },
-        { key: "/media", label: t("nav.media"), icon: GlobalOutlined },
+        { key: "/articles/imitations", label: t("nav.imitation") },
       ],
     },
     {
@@ -96,6 +113,7 @@ const navSections = computed(() => {
       key: "contentManagement",
       title: t("nav.contentManagement"),
       items: [
+        { key: "/media", label: t("nav.media"), icon: GlobalOutlined },
         { key: "/knowledge", label: t("nav.knowledge"), icon: BookOutlined },
         { key: "/images", label: t("nav.images"), icon: PictureOutlined },
       ],
@@ -124,6 +142,43 @@ const navSections = computed(() => {
   return base;
 });
 
+const headerBreadcrumbs = computed<HeaderBreadcrumb[]>(() => {
+  const currentTitle = pageTitle.value;
+  const navKey = route.meta.navKey === null ? null : String(route.meta.navKey ?? route.path);
+
+  if (!navKey) {
+    return [{ label: currentTitle }];
+  }
+
+  for (const section of navSections.value) {
+    const navItem = section.items.find((item) => item.key === navKey);
+
+    if (!navItem) {
+      continue;
+    }
+
+    const crumbs: HeaderBreadcrumb[] = [];
+    const pushCrumb = (crumb: HeaderBreadcrumb) => {
+      if (!crumb.label || crumbs.at(-1)?.label === crumb.label) {
+        return;
+      }
+      crumbs.push(crumb);
+    };
+    const isNavPage = route.path === navItem.key || currentTitle === navItem.label;
+
+    pushCrumb({ label: section.title });
+    pushCrumb({ label: navItem.label, path: isNavPage ? undefined : navItem.key });
+
+    if (!isNavPage) {
+      pushCrumb({ label: currentTitle });
+    }
+
+    return crumbs;
+  }
+
+  return [{ label: currentTitle }];
+});
+
 function go(path: string): void {
   void router.push(path);
 }
@@ -181,7 +236,29 @@ async function handleLogout(): Promise<void> {
 
     <a-layout class="admin-main-layout">
       <a-layout-header class="admin-header">
-        <h2 class="admin-header-title">{{ pageTitle }}</h2>
+        <nav class="admin-header-breadcrumb" aria-label="Breadcrumb">
+          <span
+            v-for="(crumb, index) in headerBreadcrumbs"
+            :key="`${crumb.label}-${index}`"
+            class="breadcrumb-item"
+          >
+            <span v-if="index > 0" class="breadcrumb-separator">/</span>
+            <router-link
+              v-if="crumb.path && index < headerBreadcrumbs.length - 1"
+              :to="crumb.path"
+              class="breadcrumb-link"
+            >
+              {{ crumb.label }}
+            </router-link>
+            <span
+              v-else
+              class="breadcrumb-text"
+              :class="{ 'breadcrumb-text--current': index === headerBreadcrumbs.length - 1 }"
+            >
+              {{ crumb.label }}
+            </span>
+          </span>
+        </nav>
         
         <div class="admin-header-actions">
           <div class="admin-locale-switch">
@@ -296,13 +373,55 @@ async function handleLogout(): Promise<void> {
   box-shadow: 0 1px 4px rgba(0, 21, 41, 0.08);
 }
 
-.admin-header-title {
-  margin: 0;
-  font-size: 20px;
+.admin-header-breadcrumb {
+  min-width: 0;
+  flex: 1;
+  display: flex;
+  align-items: center;
+  overflow: hidden;
+  white-space: nowrap;
+}
+
+.breadcrumb-item {
+  min-width: 0;
+  display: inline-flex;
+  align-items: center;
+}
+
+.breadcrumb-separator {
+  flex: 0 0 auto;
+  margin: 0 9px;
+  color: #bfbfbf;
+}
+
+.breadcrumb-link,
+.breadcrumb-text {
+  min-width: 0;
+  display: inline-block;
+  max-width: 220px;
+  overflow: hidden;
+  color: #8c8c8c;
+  font-size: 14px;
+  line-height: 20px;
+  text-overflow: ellipsis;
+  vertical-align: middle;
+}
+
+.breadcrumb-link {
+  transition: color 0.2s ease;
+}
+
+.breadcrumb-link:hover {
+  color: #1677ff;
+}
+
+.breadcrumb-text--current {
+  color: #141414;
   font-weight: 600;
 }
 
 .admin-header-actions {
+  flex-shrink: 0;
   display: flex;
   align-items: center;
   gap: 20px;