test(website): wait for the copy button label before reading the clipboard (#1624)

The home-sections browser test clicked `.copy-btn` and immediately asserted
`textContent() === 'Copied'`. The button flips its label only after the
asynchronous `navigator.clipboard.writeText` promise resolves, which is after
Playwright's `click()` has already returned, so a loaded CI runner sometimes
still read "Copy" (PR #1619, run 35369544094).

Poll for the label with Playwright's `expect(locator).toHaveText` (bounded
5 s) before reading the clipboard. The import is dynamic and sits after
`launchBrowser()`, so the local no-Chromium skip path is unchanged.

Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>

tools/testing/website-home-sections.test.mjs

@@ -143,14 +143,21 @@ test('browser: the download CTA and the Detected row follow the visitor OS, phon
       await page.close();
     }
 
-    // Copy buttons write the command and confirm briefly.
+    // Copy buttons write the command and confirm briefly. The label flips
+    // only after the asynchronous `navigator.clipboard.writeText` resolves,
+    // which is after `click()` has already returned, so the check has to wait
+    // for the change instead of reading the label synchronously (a loaded CI
+    // runner otherwise still sees "Copy"). `launchBrowser()` succeeding proves
+    // `@playwright/test` is importable, so this import cannot break the local
+    // no-Chromium skip above.
+    const { expect } = await import('@playwright/test');
     const context = await browser.newContext({ permissions: ['clipboard-read', 'clipboard-write'] });
     const page = await context.newPage();
     await page.goto(`${origin}${BASE}/`, { waitUntil: 'networkidle' });
     const button = page.locator('.copy-btn').first();
     await button.scrollIntoViewIfNeeded();
     await button.click();
-    assert.equal(await button.textContent(), 'Copied');
+    await expect(button).toHaveText('Copied', { timeout: 5000 });
     assert.equal(await page.evaluate(() => navigator.clipboard.readText()), 'brew install --cask iptvnator');
     await context.close();
   } finally {