feat: 统一聊天 Markdown 渲染

- 新增 ChatTimeMarkdown 并在管理端、用户端聊天入口复用

- 收敛聊天页面重复 Markdown 样式，保留工具和思考块独立渲染

easyflow-ui-admin/app/src/components/chat-history/ChatHistoryDetailDrawer.vue

@@ -509,33 +509,6 @@ async function handleCopyMessage(item: ChatTimeTimelineItem) {
 
 .chat-history-detail__markdown {
   min-width: 0;
-  font-size: 14px;
-  line-height: 1.72;
-}
-
-.chat-history-detail__markdown :deep(.markdown-body) {
-  font-size: inherit;
-  line-height: inherit;
-  background: transparent;
-}
-
-.chat-history-detail__markdown :deep(.markdown-body > :first-child) {
-  margin-top: 0;
-}
-
-.chat-history-detail__markdown :deep(.markdown-body > :last-child) {
-  margin-bottom: 0;
-}
-
-.chat-history-detail__markdown :deep(.markdown-body p) {
-  font-size: inherit;
-  line-height: inherit;
-}
-
-.chat-history-detail__markdown :deep(pre) {
-  max-width: 100%;
-  margin-top: 0;
-  overflow: auto;
 }
 
 .chat-history-detail__tool-panel :deep(.el-collapse-item__wrap) {

easyflow-ui-admin/app/src/components/chat/ChatTimeMessageContent.vue

@@ -5,9 +5,8 @@ import type {
 } from '@easyflow/types';
 
 import { computed, ref } from 'vue';
-import { XMarkdown as ElXMarkdown } from 'vue-element-plus-x';
 
-import { ChatThinkingBlock } from '@easyflow/common-ui';
+import { ChatThinkingBlock, ChatTimeMarkdown } from '@easyflow/common-ui';
 import { IconifyIcon } from '@easyflow/icons';
 
 import { CircleCheck } from '@element-plus/icons-vue';
@@ -75,7 +74,7 @@ function toggleToolExpanded() {
           :status="segment.status"
           class="chat-thinking-block-item"
         />
-        <ElXMarkdown v-else :markdown="segment.content" />
+        <ChatTimeMarkdown v-else :content="segment.content" />
       </template>
     </div>
   </template>
@@ -125,7 +124,7 @@ function toggleToolExpanded() {
     </div>
   </template>
 
-  <ElXMarkdown v-else :markdown="item.content" />
+  <ChatTimeMarkdown v-else :content="item.content" />
 </template>
 
 <style scoped>