fix: 优化导出档案系统消息宽度

- 系统消息气泡按内容自然展开，减少短消息不必要换行
- 保留容器最大宽度约束，避免窄屏横向溢出
- 增加撤回消息桌面端单行显示回归测试

src/main/export-html-template.ts

@@ -427,9 +427,11 @@ body {
 }
 .message.system .avatar { display: none; }
 .message.system .message-stack {
-  max-width: 92%;
+  width: max-content;
+  max-width: 100%;
 }
 .message.system .bubble {
+  width: max-content;
   max-width: 100%;
   padding: 5px 10px;
   border: 0;

tests/e2e/export-archive.spec.ts

@@ -805,6 +805,17 @@ test('EXPORT-ARCHIVE-03 renders shares and locations, and groups payments under
     await expect(recallNotices).toHaveCount(2)
     await expect(recallNotices.locator('.avatar')).toHaveCount(0)
     await expect(recallNotices.locator('.sender').first()).toBeHidden()
+    const recallLineMetrics = await recallNotices
+      .first()
+      .locator('.content')
+      .evaluate((element) => {
+        const styles = window.getComputedStyle(element)
+        return {
+          height: element.getBoundingClientRect().height,
+          lineHeight: Number.parseFloat(styles.lineHeight)
+        }
+      })
+    expect(recallLineMetrics.height).toBeLessThanOrEqual(recallLineMetrics.lineHeight + 1)
     const locationNotice = systemNotices.filter({ hasText: '位置共享已经结束' })
     await expect(locationNotice).toHaveCount(1)
     await expect(locationNotice.locator('.avatar')).toHaveCount(0)