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>

server/internal/tenant/prompts/loader.go

@@ -48,6 +48,9 @@ type runtimePromptsConfig struct {
 	PromptRuleTargetPlatformSupplementFormat string                         `yaml:"prompt_rule_target_platform_supplement_format"`
 	PromptRuleSupplementHeading              string                         `yaml:"prompt_rule_supplement_heading"`
 	PromptRuleOutputRequirementsSection      string                         `yaml:"prompt_rule_output_requirements_section"`
+	ArticleImitationPromptTemplate           string                         `yaml:"article_imitation_prompt_template"`
+	ArticleImitationLocaleInstructions       map[string]string              `yaml:"article_imitation_locale_instructions"`
+	ArticleImitationSettingLabels            map[string]string              `yaml:"article_imitation_setting_labels"`
 	KnowledgePromptIntroLines                []string                       `yaml:"knowledge_prompt_intro_lines"`
 	KnowledgeSnippetLabelFormat              string                         `yaml:"knowledge_snippet_label_format"`
 	KnowledgeWebsiteMarkdown                 knowledgeWebsiteMarkdownConfig `yaml:"knowledge_website_markdown"`

server/internal/tenant/prompts/runtime.go

@@ -136,6 +136,55 @@ func PromptRuleOutputRequirementsSection() string {
 	return trimPrompt(loadRuntimePrompts().PromptRuleOutputRequirementsSection)
 }
 
+func ArticleImitationPrompt(locale, sourceMeta, settingsBlock, knowledgeSection, sourceContent string) string {
+	runtime := loadRuntimePrompts()
+	template := trimPrompt(runtime.ArticleImitationPromptTemplate)
+	if template == "" {
+		template = `你是一名资深内容策略编辑，请基于给定源文章做高质量仿写创作。
+%s
+
+## 源文章
+%s
+
+## 仿写设置
+%s
+
+%s
+
+## 源文章内容
+%s
+
+请开始输出仿写后的完整文章。`
+	}
+	return strings.TrimSpace(fmt.Sprintf(
+		template,
+		ArticleImitationLocaleInstruction(locale),
+		strings.TrimSpace(sourceMeta),
+		strings.TrimSpace(settingsBlock),
+		strings.TrimSpace(knowledgeSection),
+		strings.TrimSpace(sourceContent),
+	))
+}
+
+func ArticleImitationLocaleInstruction(locale string) string {
+	instructions := loadRuntimePrompts().ArticleImitationLocaleInstructions
+	if value, ok := instructions[strings.TrimSpace(locale)]; ok && strings.TrimSpace(value) != "" {
+		return strings.TrimSpace(value)
+	}
+	if strings.EqualFold(strings.TrimSpace(locale), "en-US") {
+		return "Output language: English."
+	}
+	return "输出语言：中文简体。"
+}
+
+func ArticleImitationSettingLabel(key string) string {
+	labels := loadRuntimePrompts().ArticleImitationSettingLabels
+	if value, ok := labels[strings.TrimSpace(key)]; ok && strings.TrimSpace(value) != "" {
+		return strings.TrimSpace(value)
+	}
+	return strings.TrimSpace(key)
+}
+
 func KnowledgePromptIntroLines() []string {
 	lines := loadRuntimePrompts().KnowledgePromptIntroLines
 	return append([]string(nil), lines...)