test(streak route): verify SVG contains <title> element for accessibility (JhaSourav07#1118)

## Description
Fixes JhaSourav07#701

## Pillar
- [ ] 🎨 Pillar 1 — New Theme Design
- [ ] 📐 Pillar 2 — Geometric SVG Improvement
- [ ] 🕐 Pillar 3 — Timezone Logic Optimization
- [x] 🛠️ Other (Bug fix, refactoring, docs)

## Visual Preview
N/A — test-only change.

## Checklist before requesting a review:
- [x] I have read the `CONTRIBUTING.md` file.
- [x] I have tested these changes locally
(`localhost:3000/api/streak?user=YOUR_USERNAME`).
- [x] I have run `npm run format` and `npm run lint` locally and
resolved all errors (CI will fail otherwise).
- [x] My commits follow the Conventional Commits format (e.g.,
`feat(themes): ...`, `fix(calculate): ...`).
- [x] I have updated `README.md` if I added a new theme or URL
parameter. N/A.
- [x] I have started the repo.
- [x] I have made sure that i have only one commit to merge in this PR.
- [x] The SVG output matches the CommitPulse "premium quality" aesthetic
standard (no raw elements, smooth animations, correct fonts). N/A.
- [x] (Recommended) I joined the CommitPulse Discord community for
contributor discussions, mentorship, and faster PR support.

Author: JhaSourav07

app/api/streak/route.test.ts

@@ -151,6 +151,14 @@ describe('GET /api/streak', () => {
       // The generator puts params.user.toUpperCase() in the SVG as the badge title.
       expect(body).toContain('OCTOCAT');
     });
+
+    it('should contain a <title> element with accessible label in the SVG response', async () => {
+      const response = await GET(makeRequest({ user: 'octocat' }));
+      const body = await response.text();
+
+      expect(body).toContain('<title>');
+      expect(body).toContain('Stats for');
+    });
   });
 
   describe('cache-control header', () => {