test(notifications): the center re-says its rows after a switch, a repeat coalesces by content; e2e helper fails with a cause

The center's rows (title, message, refusal, live button) were never rendered across a language
switch, and nothing held the structural compare that coalescing now needs. The channel-link helper
swallowed whatever ended its poll into a bare false: a link that goes away mid-look now counts as
not hit, and no hittable link fails with the poll's own message.

frontend/e2e/bookmark.spec.ts

@@ -196,7 +196,7 @@ test.describe("a bookmark reopens the view it was taken of", () => {
   test("a channel page's own tab, over the page it was opened from", async ({ page, browser }) => {
     await openApp(page, "/?page=feed");
     await expect(page.getByTestId("video-card").first()).toBeVisible();
-    expect(await clickVisibleChannelLink(page)).toBe(true);
+    await clickVisibleChannelLink(page);
     const title = await page.getByTestId("channel-title").textContent();
     await tab(page, "About").click();
     const fresh = await bookmarked(browser, page);