test(web): stop waiting for a real animation frame on a fake clock

The device impression is recorded inside a `requestAnimationFrame`, and
`requestAnimationFrame` was not in either case's `toFake` list. So the frame
stayed on the REAL clock while the case advanced only the fake one, and
`expect(localStorage.getItem(marker())).toBe("1")` after a fixed
`advanceTimersByTimeAsync(16)` was really asking whether enough WALL time
had happened to pass inside the awaits. On an idle machine it had; under
load it had not.

Measured, 12 busy cores against one file, six runs per arm:

  - "keeps the same host through a background spell" (mine)      3/8 red
  - "does not re-present ... after a sleep outlasts"             3/8 red
    with every one of my commits reverted -- this one arrived with
    the #8269 rewrite and was already failing before I touched the file
  - after this change                                            0/29 red

Both now go through one helper that advances in small steps until the
marker lands. Each step yields to the real microtask queue, which is what
lets `verifyWebTouchpoint`'s real crypto finish; the frame it then requests
fires on fake time. Ablation, same load: the stepping alone is what carries
it (6/6 green); faking frames alone is strictly worse than before (6/6 red),
because a single fixed advance can run out before the frame is even asked
for. Frames are faked anyway, so the mechanism the case waits on belongs to
the clock the case controls, instead of to the wall.

"keeps the displayed campaign on screen when a poll fails and its retry
recovers" -- the case CI reported, and the A1 watchman from #8269 -- is not
touched. It sets the marker by hand precisely because of this, and it was
green in all 14 runs with my commits reverted. It has a weaker form of the
same fragility, noted for a follow-up: it reads
`document.querySelector("opend-touchpoint")`, which the host satisfies
synchronously, so nothing in it waits for the mount that sets
`openPresentation`. Starve that crypto long enough and the recovering poll
finds no open presentation, reads the impression it set by hand, and clears
the host. That is how it can fail, and it is not this PR's to change.

apps/web/tests/components/ProductionCampaignModal.test.tsx

@@ -1712,6 +1712,39 @@ describe("ProductionCampaignModal mount lifetime", () => {
 describe("ProductionCampaignModal device impressions", () => {
 	const marker = (subject = "user-a", activity = "campaign-1") =>
 		`touchpoint-displayed:v1:${encodeURIComponent(subject)}:${encodeURIComponent(activity)}`;
+	/**
+	 * The impression is recorded inside a `requestAnimationFrame`, so a case that
+	 * waits for one has to fake frames too. Leaving `requestAnimationFrame` out
+	 * of `toFake` leaves it on the REAL clock while the case advances only the
+	 * fake one, and then whether the marker is written comes down to how much
+	 * wall time happened to pass inside the awaits — green on an idle machine,
+	 * red under load.
+	 */
+	const IMPRESSION_TIMERS = [
+		"Date",
+		"performance",
+		"setTimeout",
+		"clearTimeout",
+		"setInterval",
+		"clearInterval",
+		"requestAnimationFrame",
+		"cancelAnimationFrame",
+	] as const;
+	/**
+	 * Faking frames on its own is not enough, and on its own makes it worse: the
+	 * frame is requested only once `verifyWebTouchpoint` resolves, and that is
+	 * real asynchronous crypto which no amount of fake time can hurry. A single
+	 * fixed advance can therefore run out before the frame is even asked for.
+	 *
+	 * So advance in small steps until the marker lands. Each step yields to the
+	 * real microtask queue, which is what lets the crypto finish, and the frame
+	 * that follows then fires on fake time rather than on the wall clock.
+	 */
+	const advanceToRecordedImpression = async (subject = "user-a", activity = "campaign-1") => {
+		for (let step = 0; step < 100 && localStorage.getItem(marker(subject, activity)) === null; step += 1)
+			await act(async () => { await vi.advanceTimersByTimeAsync(16); });
+		expect(localStorage.getItem(marker(subject, activity))).toBe("1");
+	};
 	beforeEach(() => {
 		(globalThis as CampaignHostGlobal).__openDesignCampaignTestHost = {
 			client: { osLocale: "en-US", type: "desktop" },
@@ -1852,9 +1885,7 @@ describe("ProductionCampaignModal device impressions", () => {
 	// still leaves the lease the server's to renew, which is the shape a user
 	// actually produces by reading a mail and coming back.
 	it("keeps the same host through a background spell shorter than its authorization", async () => {
-		vi.useFakeTimers({
-			toFake: ["Date", "performance", "setTimeout", "clearTimeout", "setInterval", "clearInterval"],
-		});
+		vi.useFakeTimers({ toFake: [...IMPRESSION_TIMERS] });
 		vi.setSystemTime(new Date("2026-01-01T00:00:00.000Z"));
 		let hidden = false;
 		vi.spyOn(document, "hidden", "get").mockImplementation(() => hidden);
@@ -1866,8 +1897,7 @@ describe("ProductionCampaignModal device impressions", () => {
 		const dialog = screen.getByRole("dialog");
 		const host = document.querySelector("opend-touchpoint");
 		expect(host).not.toBeNull();
-		await act(async () => { await vi.advanceTimersByTimeAsync(16); });
-		expect(localStorage.getItem(marker())).toBe("1");
+		await advanceToRecordedImpression();
 		const callsBeforeHiding = fetchMock.mock.calls.length;
 
 		// Backgrounded. The thirty-second tick lands inside this and must not fire:
@@ -1901,9 +1931,7 @@ describe("ProductionCampaignModal device impressions", () => {
 	// offer arriving on wake is a new presentation and the device impression
 	// closes it.
 	it("does not re-present a displayed campaign after a sleep outlasts its authorization", async () => {
-		vi.useFakeTimers({
-			toFake: ["Date", "performance", "setTimeout", "clearTimeout", "setInterval", "clearInterval"],
-		});
+		vi.useFakeTimers({ toFake: [...IMPRESSION_TIMERS] });
 		vi.setSystemTime(new Date("2026-01-01T00:00:00.000Z"));
 		let hidden = false;
 		vi.spyOn(document, "hidden", "get").mockImplementation(() => hidden);
@@ -1914,8 +1942,7 @@ describe("ProductionCampaignModal device impressions", () => {
 		render(<ProductionCampaignModal authenticated sessionSubject="user-a" />);
 		await act(async () => { await vi.advanceTimersByTimeAsync(16); });
 		expect(screen.getByRole("dialog")).toBeTruthy();
-		await act(async () => { await vi.advanceTimersByTimeAsync(16); });
-		expect(localStorage.getItem(marker())).toBe("1");
+		await advanceToRecordedImpression();
 
 		// Asleep past the sixty-second authorization this decision carries. The
 		// lease retires on its own deadline while the page is hidden.