test(ui): stabilize cross-browser suite

- Run visual snapshots on Chromium only; Firefox/WebKit rendering does
  not match Chromium pixel output. Functional and accessibility
  assertions still run on all four projects (baselines were renamed to
  the new project names in the previous commit).
- Poll axe audits until clean: WebKit can report stale color-contrast
  violations for a moment after interactions while styles settle.
- Poll the Tab-focus assertion: Firefox can swallow a Tab while the
  sandboxed srcdoc preview frame is still loading.
- Fix the recovery clock race: install the fake clock before navigation
  at a fixed time and pause at a fixed target instead of wall-clock
  values, which under load could already be in the fake clock's past
  ('Cannot fast-forward to the past').

e2e/ui/draft-recovery.spec.ts

@@ -116,9 +116,14 @@ test("saving while recovery is pending enables recovery for subsequent edits", a
 test("unmount flush retains an edit before the autosave interval", async ({
 	page,
 }) => {
+	// Install the fake clock before navigation so every page timer is faked,
+	// then jump forward to a fixed pause point. Using wall-clock `new Date()`
+	// for both calls raced under load: the fake clock ticks in real time
+	// between the calls and can pass the target ("Cannot fast-forward to the
+	// past"). The 60s jump only fires no-op persists on a clean form.
+	await page.clock.install({ time: new Date("2030-01-01T12:00:00Z") });
 	await page.goto("/admin/articles/recovery");
-	await page.clock.install();
-	await page.clock.pauseAt(new Date());
+	await page.clock.pauseAt(new Date("2030-01-01T12:01:00Z"));
 	await page.locator('input[name="title"]').fill("Immediate final edit");
 	await page
 		.getByRole("button", { name: "Close editor fixture", exact: true })