fix(e2e): skip desktop-sidebar specs on mobile + stub /api/dashboard/widgets

Three remaining e2e failures after the global-setup tour-completed fix
all came from cross-project sharing — specs that target desktop-only
DOM (the `aside[aria-label="Sidebar"]` logo + Achievements link)
were running in the chromium-mobile profile too, where the sidebar
is `hidden md:flex` by design. Added `test.skip(viewport.width < 768,
...)` guards so each spec only runs in the project that can satisfy
its contract.

The fourth failure was the `/api/dashboard/widgets` endpoint that the
A5 tile-strip work added since `onboarding-flicker.spec.ts` was
written. Without a stub the unauthenticated dashboard 500s on this
query and React Query's error boundary swallows the page render
before `<GettingStartedChecklist>` mounts. Added the stub to both
flicker specs (complete + incomplete-onboarding paths).

e2e/a11y.spec.ts

@@ -119,7 +119,19 @@ test.describe("axe-core authenticated surfaces", () => {
   // bounding box must accept the click.
   test("skip-link does not block logo click outside focus", async ({
     page,
+    viewport,
   }) => {
+    // The desktop sidebar (and its logo) is `hidden md:flex` — the
+    // mobile profile (Pixel 5) hides it by design. The skip-link
+    // regression Marc originally reported in v1.4.14 was a desktop-
+    // only artifact (mobile uses the topbar logo, which is a
+    // different DOM node). Skip the mobile project so we don't
+    // flake on a contract that doesn't apply there.
+    test.skip(
+      (viewport?.width ?? 0) < 768,
+      "desktop sidebar logo is hidden on mobile by design",
+    );
+
     await page.goto("/", { waitUntil: "domcontentloaded" });
     await page.waitForLoadState("networkidle");
 

e2e/achievements.spec.ts

@@ -55,11 +55,23 @@ test.describe("achievements page is reachable from the sidebar", () => {
     );
   });
 
-  test("desktop sidebar exposes the achievements link", async ({ page }) => {
+  test("desktop sidebar exposes the achievements link", async ({
+    page,
+    viewport,
+  }) => {
+    // The sidebar nav is hidden on small viewports (`md:flex`). The
+    // chromium-mobile profile (Pixel 5, 393 px wide) cannot satisfy
+    // this contract by design — skip there so the spec only runs in
+    // the chromium-desktop project (1280×720). Without this guard
+    // every push fails 1 / 4 specs purely because the same suite is
+    // sharded across both projects.
+    test.skip(
+      (viewport?.width ?? 0) < 768,
+      "sidebar is hidden on mobile by design (md:flex breakpoint)",
+    );
+
     await page.goto("/", { waitUntil: "domcontentloaded" });
-    // The sidebar nav is hidden on small viewports (`md:flex`); the
-    // chromium-desktop project uses 1280×720 so it's visible here. Match
-    // by aria-label so we don't accidentally pick up a tooltip.
+    // Match by aria-label so we don't accidentally pick up a tooltip.
     const sidebar = page.locator('aside[aria-label="Sidebar"]');
     await expect(sidebar).toBeVisible();
     await sidebar.getByRole("link", { name: "Achievements" }).click();

e2e/onboarding-flicker.spec.ts

@@ -94,6 +94,19 @@ test.describe("dashboard onboarding card flicker guard", () => {
         }),
       }),
     );
+    // Same `/api/dashboard/widgets` stub as the incomplete-onboarding
+    // test below — keeps the dashboard from error-boundary-bailing
+    // when this query 500s in CI without a real session.
+    await page.route("**/api/dashboard/widgets", (route) =>
+      route.fulfill({
+        status: 200,
+        contentType: "application/json",
+        body: JSON.stringify({
+          data: { tilesVisible: { weight: true, bp: true, pulse: true } },
+          error: null,
+        }),
+      }),
+    );
 
     const card = page.locator('[data-testid="onboarding-card"]');
 
@@ -192,6 +205,21 @@ test.describe("dashboard onboarding card flicker guard", () => {
         body: JSON.stringify({ data: { channels: [] }, error: null }),
       }),
     );
+    // v1.4.16 Wave-C — the dashboard added `/api/dashboard/widgets`
+    // (A5 tile-strip persistence) since this spec was written. Without
+    // a stub the unauthenticated layout query 500s in CI and React
+    // Query's error boundary swallows the page render before
+    // `<GettingStartedChecklist>` can mount.
+    await page.route("**/api/dashboard/widgets", (route) =>
+      route.fulfill({
+        status: 200,
+        contentType: "application/json",
+        body: JSON.stringify({
+          data: { tilesVisible: { weight: true, bp: true, pulse: true } },
+          error: null,
+        }),
+      }),
+    );
 
     // Make sure no localStorage carries an `expanded=1` from a previous
     // session — the spec asserts the *default* is collapsed.