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/i18n/messages/en-US.ts

@@ -71,6 +71,7 @@ const enUS = {
     templates: "Templates",
     custom: "Custom Generation",
     freeCreate: "Free Create",
+    imitation: "Imitation Create",
     media: "Media",
     brandManagement: "Brand Management",
     brands: "Brand Library",
@@ -150,6 +151,14 @@ const enUS = {
       title: "Free Create",
       description: "Create and edit articles freely, no templates or AI generation required.",
     },
+    imitation: {
+      title: "Imitation Create",
+      description: "Manage rewritten articles generated from citation sources or external URLs.",
+    },
+    imitationCreate: {
+      title: "Imitation Create",
+      description: "Extract an article from a URL, then generate a new article in one step.",
+    },
     media: {
       title: "Media Management",
       description: "Review desktop-managed media bindings, authorization state, and sync results in one place.",
@@ -385,6 +394,7 @@ const enUS = {
     citationAnalysisTitle: "Citation Analysis",
     contentCitations: "Content Citations",
     contentCitationsTitle: "Content Citations",
+    imitationAction: "Imitation create",
     taskDebugTitle: "Async Task Debug",
     taskDebugHint: "For troubleshooting the callback -> queue -> worker flow only. The four main content sections above stay unchanged.",
     contentCitationBadge: "Content Citation",
@@ -551,9 +561,76 @@ const enUS = {
       instant_task: "Instant task",
       schedule_task: "Scheduled task",
       free_create: "Free create",
+      imitation: "Imitation create",
       kol: "Refined template generation",
     },
   },
+  imitation: {
+    actions: {
+      create: "New Rewrite",
+      submit: "Submit and generate",
+    },
+    filters: {
+      publishStatus: "Publish status",
+      generateStatus: "Generation status",
+      keyword: "Search",
+      createdTime: "Created time",
+      createdTimeStart: "Start time",
+      createdTimeEnd: "End time",
+      keywordPlaceholder: "Search by article title",
+    },
+    list: {
+      eyebrow: "Imitation Create",
+      count: "{count} articles",
+      sourceArticle: "Source",
+      empty: "No rewritten articles yet. Start from a citation source or create one manually.",
+      deleteConfirm: "Delete this rewritten article?",
+      deleteSuccess: "Article deleted.",
+      deleteError: "Failed to delete article.",
+    },
+    create: {
+      title: "Create rewritten article",
+      subtitle: "The backend fetches the source article first, then generates a new original article from your settings.",
+      sourceSection: "Source article",
+      settingsSection: "Rewrite settings",
+      sourceURL: "Article URL",
+      sourceTitle: "Source title",
+      language: "Article language",
+      industry: "Industry / scenario",
+      brandName: "Brand / subject",
+      region: "Region",
+      targetAudience: "Target audience",
+      contentGoal: "Content goal",
+      tone: "Tone",
+      lengthGoal: "Length",
+      keywords: "Keywords",
+      preservePoints: "Keep / emphasize",
+      avoidPoints: "Avoid",
+      extraRequirements: "Extra requirements",
+      enableWebSearch: "Allow web search supplement",
+      webSearchHint: "When enabled, generation can reference live web information for newer facts or industry context.",
+      knowledgeBase: "Reference knowledge base",
+      knowledgeBasePlaceholder: "Optional. Add facts, brand material, and industry background.",
+      knowledgeBaseHint: "Selected groups are retrieved in the backend and passed to generation as reference context.",
+      sourceURLPlaceholder: "https://example.com/article",
+      sourceTitlePlaceholder: "Optional. Citation titles are prefilled automatically.",
+      industryPlaceholder: "For example: home improvement, education, SaaS, healthcare",
+      brandNamePlaceholder: "Optional. Helps the article fit a specific brand or subject.",
+      regionPlaceholder: "For example: Shanghai, East China, nationwide, North America",
+      targetAudiencePlaceholder: "For example: first-time buyers, channel partners, procurement leads",
+      contentGoalPlaceholder: "For example: education, conversion, brand trust, selection advice",
+      tonePlaceholder: "For example: professional, conversational, comparative, news analysis",
+      lengthGoalPlaceholder: "For example: around 1200 words, short post, long-form guide",
+      keywordsPlaceholder: "Type keywords and press Enter",
+      preservePointsPlaceholder: "List facts, data, arguments, or examples that must be kept.",
+      avoidPointsPlaceholder: "List claims, competitors, compliance risks, or wording to avoid.",
+      extraRequirementsPlaceholder: "Add channel, structure, title style, or industry-specific instructions.",
+      queued: "Rewrite task submitted and queued.",
+      sourceURLRequired: "Enter the source article URL first.",
+      submitError: "Failed to submit rewrite task.",
+      backToList: "Back to rewrites",
+    },
+  },
   freeCreate: {
     actions: {
       create: "New Article",
@@ -856,6 +933,7 @@ const enUS = {
       templateType: "Template",
       currentVersion: "Current version",
       source: "Source label",
+      sourceArticle: "Source article",
       wordCount: "Word count",
     },
     versionUntitled: "Untitled version",