fix: stack footer links vertically on mobile

Wrapped inline links produced a ragged two-line block with small tap targets.
Links now stack in a single column below sm and return to one row above it.

E2e asserts both directions: every link has a distinct y at 375px, and they
share a row at 1280px.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

web/components/shared/footer.tsx

@@ -36,7 +36,9 @@ export default function Footer() {
           </span>
         </div>
 
-        <nav className='flex flex-wrap items-center justify-center gap-x-5 gap-y-2'>
+        {/* Stacked on mobile: wrapped inline links produced a ragged two-line
+            block that was hard to scan and gave small tap targets. */}
+        <nav className='flex w-full flex-col items-center gap-3 sm:w-auto sm:flex-row sm:flex-wrap sm:justify-center sm:gap-x-5 sm:gap-y-2'>
           {links.map((link) => (
             <Link
               key={link.label}

web/e2e/chrome.spec.ts

@@ -61,6 +61,40 @@ test.describe('app chrome (mocked API, no real backend)', () => {
     ).toBeLessThanOrEqual(tabBarBox!.y + 1)
   })
 
+  test('mobile: footer links stack vertically', async ({ page, context }) => {
+    await page.setViewportSize({ width: 375, height: 800 })
+    await authenticate(context)
+    await mockApi(page)
+    await page.goto('/dashboard')
+
+    const links = page.locator('footer nav a')
+    const count = await links.count()
+    expect(count).toBeGreaterThan(2)
+
+    // Stacked means every link sits on its own row, so each y is distinct.
+    const ys: number[] = []
+    for (let i = 0; i < count; i += 1) {
+      const box = await links.nth(i).boundingBox()
+      expect(box).not.toBeNull()
+      ys.push(Math.round(box!.y))
+    }
+    expect(new Set(ys).size, 'each footer link should be on its own row').toBe(
+      count
+    )
+  })
+
+  test('desktop: footer links sit on one row', async ({ page, context }) => {
+    await page.setViewportSize({ width: 1280, height: 900 })
+    await authenticate(context)
+    await mockApi(page)
+    await page.goto('/dashboard')
+
+    const links = page.locator('footer nav a')
+    const first = await links.first().boundingBox()
+    const last = await links.last().boundingBox()
+    expect(Math.abs(first!.y - last!.y)).toBeLessThan(8)
+  })
+
   test('top bar is reduced to brand and account', async ({ page, context }) => {
     await authenticate(context)
     await mockApi(page)