test(web): un-skip discover/requests route tests — mock $app (#374)

Root cause: discover.test.ts and requests.test.ts were the only route
page tests NOT mocking $app/state (+ $app/navigation), so rendering
the +page.svelte pulled in SvelteKit's client runtime and threw
`TypeError: notifiable_store is not a function` at module load. They'd
been describe.skip'd AND hard-excluded in vitest.config.ts.

Fix mirrors every other route test: vi.hoisted pageState +
vi.mock('$app/state', () => pageUrlModule(state)) +
vi.mock('$app/navigation', () => ({ goto: vi.fn() })). Un-skip both
describe blocks; drop the vitest.config exclude. The web test job
now runs both suites again.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

web/vitest.config.ts

@@ -7,19 +7,7 @@ export default defineConfig({
   test: {
     environment: 'jsdom',
     include: ['src/**/*.test.ts', 'src/**/*.svelte.test.ts', 'scripts/**/*.test.js'],
-    // M7 #374: these two test files explode at module-load with
-    // `TypeError: notifiable_store is not a function` from SvelteKit's
-    // internal client.js — the import chain triggers SvelteKit's client
-    // runtime init in a way the dev-push vitest invocation can't satisfy.
-    // describe.skip inside the files doesn't help because vitest must
-    // load the file before it can see the describe block. Excluded here
-    // until the triage in #374 lands a real fix (probably a $app/paths
-    // mock in vitest.setup.ts).
-    exclude: [
-      ...configDefaults.exclude,
-      'src/routes/discover/discover.test.ts',
-      'src/routes/requests/requests.test.ts'
-    ],
+    exclude: [...configDefaults.exclude],
     setupFiles: ['./vitest.setup.ts']
   }
 });