test(svg): add accessibility metadata assertions for SVG output (JhaSourav07#463)

## Description

Fixes JhaSourav07#400 
## Changes made

- Added accessibility-focused test coverage for SVG `<title>` and
`<desc>` metadata
- Verified `<title>` contains the username
- Verified `<desc>` includes total contributions and longest streak
values
- Ensured all existing tests continue to pass
## Pillar

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

## Visual Preview

## 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.
- [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).
- [x] (Recommended) I joined the CommitPulse Discord community for
contributor discussions, mentorship, and faster PR support.

Author: JhaSourav07

lib/svg/generator.test.ts

@@ -376,6 +376,18 @@ describe('generateSVG', () => {
 
       expect(svg).not.toContain('attributeName="opacity" values="1;0.4;1"');
     });
+    it('includes accessible title and description metadata', () => {
+      const svg = generateSVG(
+        mockStats,
+        { user: 'octocat' } as unknown as BadgeParams,
+        mockCalendar
+      );
+
+      expect(svg).toContain('<title>CommitPulse Stats for octocat</title>');
+      expect(svg).toContain('<desc>');
+      expect(svg).toContain('100');
+      expect(svg).toContain('10');
+    });
   });
 
   describe('tower top highlight', () => {