fix: show teacher introductions as standalone clickable bubbles

tests/e2e/community-welcome.spec.ts

@@ -65,7 +65,7 @@ for (const width of [375, 768, 1280, 1470]) {
     await page.getByTestId('community-invitation').scrollIntoViewIfNeeded();
     expect(await page.evaluate(() => document.documentElement.scrollWidth)).toBeLessThanOrEqual(width);
     await expect(page.getByRole('button', { name: '去作品广场逛逛' })).toBeVisible();
-    await teachers.getByRole('button', { name: '先自己试试' }).click();
+    while (await teachers.count()) await teachers.getByRole('button', { name: /^收起.*的介绍$/ }).first().click();
     await heading.scrollIntoViewIfNeeded();
     const composer = page.getByTestId('coding-message-composer');
     await expect(composer).toBeInViewport({ ratio: 1 });
@@ -125,7 +125,7 @@ for (const width of [1280, 1470]) {
     }).toBeLessThan(2);
     const inputBeforeDismiss = await composer.boundingBox();
     const headingBeforeDismiss = await heading.boundingBox();
-    await teachers.getByRole('button', { name: '先自己试试' }).click();
+    while (await teachers.count()) await teachers.getByRole('button', { name: /^收起.*的介绍$/ }).first().click();
     await expect(composer.getByRole('textbox')).toHaveValue('保留这份草稿');
     expect(await composer.boundingBox()).toEqual(inputBeforeDismiss);
     expect(await heading.boundingBox()).toEqual(headingBeforeDismiss);