Improve test coverage of frontend files

[anurag2787]

Describe the bug
The latest frontend unit test run shows strong overall coverage, but several individual files remain below the 80% line coverage threshold. This issue aims improving coverage for those files

Files requiring improved coverage

No coverage (0%)

• src/app/not-found.tsx
• src/components/DashboardWrapper.tsx
• src/components/FontLoaderWrapper.tsx
• src/components/StructuredDataScript.tsx

Low coverage (<60%)

• src/components/ModuleCard.tsx
• src/components/ChapterMapWrapper.tsx

Moderate coverage (60–79%)

• src/app/global-error.tsx
• src/app/about/page.tsx
• src/app/contribute/page.tsx
• src/app/my/mentorship/page.tsx
• src/app/my/mentorship/programs/[programKey]/edit/page.tsx
• src/app/my/mentorship/programs/create/page.tsx
• src/app/projects/dashboard/metrics/page.tsx
• src/components/CalendarButton.tsx
• src/components/CardDetailsPage.tsx
• src/components/ContributionHeatmap.tsx
• src/components/Header.tsx
• src/components/InfoItem.tsx
• src/components/LabelList.tsx
• src/components/Leaders.tsx
• src/components/MentorshipPullRequest.tsx
• src/components/MetricsPDFButton.tsx
• src/components/ProgramCard.tsx
• src/components/ProgramForm.tsx
• src/components/Release.tsx
• src/components/RepositoryCard.tsx
• src/components/Search.tsx
• src/components/SkeletonsBase.tsx
• src/components/TruncatedText.tsx
• src/components/UserMenu.tsx
• src/components/forms/shared/FormButtons.tsx
• src/components/forms/shared/formValidationUtils.ts

Are you going to work on fixing this?

• Yes
• No