feat(explorer): API-driven CCIP route catalog on bridge page

Load destination bridge contracts from token-aggregation, add fallback polling,
extend smoke tests, and document bridge routes client helper.

Co-authored-by: Cursor <cursoragent@cursor.com>

scripts/e2e-sprint-smoke.spec.ts

@@ -31,4 +31,10 @@ test.describe('Explorer sprint smoke', () => {
     await expect(page.getByRole('heading', { name: /Operations Hub/i })).toBeVisible({ timeout: 10000 })
     await expect(page.getByText(/Extended Metamask dual-chain catalog/i).first()).toBeVisible({ timeout: 10000 })
   })
+
+  test('bridge page loads CCIP route catalog', async ({ page }) => {
+    await page.goto(`${EXPLORER_URL}/bridge`, { waitUntil: 'domcontentloaded', timeout: 30000 })
+    await expect(page.getByRole('heading', { name: /Bridge & Relay Monitoring/i })).toBeVisible({ timeout: 15000 })
+    await expect(page.getByText(/CCIP route catalog/i).first()).toBeVisible({ timeout: 15000 })
+  })
 })