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-usercenter/app/src/components/chat/bubbleList.vue

@@ -1,11 +1,9 @@
 <script setup lang="ts">
 import type { ChatTimeTimelineItem } from '@easyflow/types';
 
-import { XMarkdown as ElXMarkdown } from 'vue-element-plus-x';
-
 import { computed, ref } from 'vue';
 
-import { ChatThinkingBlock } from '@easyflow/common-ui';
+import { ChatThinkingBlock, ChatTimeMarkdown } from '@easyflow/common-ui';
 import { IconifyIcon } from '@easyflow/icons';
 import { useUserStore } from '@easyflow/stores';
 
@@ -200,7 +198,7 @@ async function handleCopy(item: ChatTimeTimelineItem) {
               :status="segment.status"
               class="chat-thinking-block-item"
             />
-            <ElXMarkdown v-else :markdown="segment.content" />
+            <ChatTimeMarkdown v-else :content="segment.content" />
           </template>
         </div>
       </template>
@@ -256,7 +254,7 @@ async function handleCopy(item: ChatTimeTimelineItem) {
           </div>
         </div>
       </template>
-      <ElXMarkdown v-else :markdown="item.content" />
+      <ChatTimeMarkdown v-else :content="item.content" />
     </template>
 
     <template #footer="{ item }">