test(svg): add year parameter route test (JhaSourav07#613)

## Description

Fixes JhaSourav07#365

Added a test case to verify that the `?year=` parameter correctly passes
the expected `from` and `to` date range values to
`fetchGitHubContributions`.

## Changes made

* Added route test for `?year=2023`
* Asserted correct date range:

  * `from: '2023-01-01T00:00:00Z'`
  * `to: '2023-12-31T23:59:59Z'`

## 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 changes)

## Checklist before requesting a review:

- [x] I have read the `CONTRIBUTING.md` file.
- [x] I have tested these changes locally.
- [x] I have run `npm run format` and `npm run lint` locally and
resolved all errors.
- [x] My commits follow the Conventional Commits format.
- [ ] 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.
- [x] I joined the CommitPulse Discord community for contributor
discussions, mentorship, and faster PR support.

Author: JhaSourav07

app/api/streak/route.test.ts

@@ -249,6 +249,16 @@ describe('GET /api/streak', () => {
       expect(response.status).toBe(200);
     });
 
+    it('passes correct from/to range when ?year=2023 is provided', async () => {
+      await GET(makeRequest({ user: 'octocat', year: '2023' }));
+
+      expect(fetchGitHubContributions).toHaveBeenCalledWith('octocat', {
+        bypassCache: false,
+        from: '2023-01-01T00:00:00Z',
+        to: '2023-12-31T23:59:59Z',
+      });
+    });
+
     it('functions normally when the year parameter is missing', async () => {
       const response = await GET(makeRequest({ user: 'octocat' }));