feat: Markdown 引用注入法 - AI回复自动拼接引用块（主题无关通用方案）

- 后端 CommentReplyPublisher.doPublish 重写，发布前查询被回复对象并拼接 Markdown Blockquote
- 新增 buildQuoteMarkdown 辅助方法，Jsoup 清除 HTML 后截断 40 字符生成引用
- 前端 LogsView 恢复简洁气泡模板，移除 quoteOwner/quoteContent 前端引用逻辑
- renderContent 新增换行符处理，确保 Markdown 引用块正确渲染

ui/src/views/LogsView.vue

@@ -299,19 +299,8 @@
                     :class="msg.isAi
                       ? 'bg-blue-50 text-gray-800 rounded-tl-md'
                       : 'bg-gray-100 text-gray-800 rounded-tr-md'"
-                  >
-                    <!-- 引用摘要模块（仅当存在引用时显示） -->
-                    <div
-                      v-if="msg.quoteOwner && msg.quoteContent"
-                      class="mb-2 px-3 py-1.5 bg-black/5 rounded-lg border-l-2 border-gray-300 text-xs text-gray-500"
-                    >
-                      <span class="font-medium text-gray-600">@{{ msg.quoteOwner }}</span>:
-                      {{ truncateQuote(msg.quoteContent, 30) }}
-                    </div>
-
-                    <!-- 实际回复内容 -->
-                    <div v-html="renderContent(msg.content)"></div>
-                  </div>
+                    v-html="renderContent(msg.content)"
+                  ></div>
                   <!-- Time -->
                   <div class="text-[10px] text-gray-300 mt-1" :class="msg.isAi ? 'text-left' : 'text-right'">
                     {{ formatDate(msg.time) }}
@@ -369,8 +358,6 @@ interface ConversationMessage {
   content: string
   time: string
   isAi: boolean
-  quoteOwner?: string
-  quoteContent?: string
 }
 
 const replies = ref<AiCommentReplyItem[]>([])
@@ -652,15 +639,6 @@ const stripHtml = (html: string) => {
     .trim()
 }
 
-/**
- * Truncate quote content for preview
- */
-const truncateQuote = (content: string, length = 30) => {
-  if (!content) return ""
-  const plain = stripHtml(content)
-  return plain.length > length ? plain.substring(0, length) + "..." : plain
-}
-
 /**
  * Sanitize and render HTML content for conversation bubbles.
  * Only allows safe inline tags, strips dangerous elements.
@@ -668,6 +646,8 @@ const truncateQuote = (content: string, length = 30) => {
 const renderContent = (content: string) => {
   if (!content) return "<span class='text-gray-400'>(空)</span>"
   return content
+    // 将 Markdown 的换行符替换为 HTML 的换行
+    .replace(/\n/g, "<br/>")
     .replace(/<script[^>]*>[\s\S]*?<\/script>/gi, "")
     .replace(/<iframe[^>]*>[\s\S]*?<\/iframe>/gi, "")
     .replace(/<object[^>]*>[\s\S]*?<\/object>/gi, "")