Fix/remove duplicate footer links 2799

[desireddymohithreddy0925]

Summary

Fixes the Footer component by removing the redundant hardcoded "Product" navigation links. The "Dashboard" authentication logic has been moved inside the PRODUCT_LINKS mapped loop to prevent duplicated links while preserving functionality.

Closes #2799

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Type of Change

• 🐛 Bug fix (non-breaking change that fixes an issue)
• ✨ New feature (non-breaking change that adds functionality)
• 💥 Breaking change (fix or feature that changes existing behavior)
• 📝 Documentation update
• ♻️ Refactor / code cleanup (no functional change)
• ⚡ Performance improvement
• 🔒 Security fix
• 🧪 Tests only

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What Changed

• src/components/Footer.tsx: Removed the hardcoded duplicate block of "Home", "Dashboard", "Leaderboard", and "Contact" links.
• src/components/Footer.tsx: Updated FooterLink component to support the onClick prop, rendering a stylistically identical <button> instead of a <Link> when provided.
• src/components/Footer.tsx: Intercepted the "Dashboard" iteration in the PRODUCT_LINKS.map loop to trigger the GitHub signIn action if the user is unauthenticated, replicating the old functionality cleanly.

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How to Test

1. Check out the branch and run the development server (npm run dev).
2. Navigate to the homepage or dashboard while unauthenticated and scroll down to the Footer.
3. Observe that the Product section has exactly one set of links (Home, Dashboard, Leaderboard, Contact).
4. Click on the "Dashboard" link and ensure it triggers the GitHub authentication redirect.
5. Log in (authenticate) and verify the "Dashboard" link in the footer routes to /dashboard directly without triggering auth again.

Expected result:
The footer looks clean without duplicated links, and unauthenticated users can click "Dashboard" to sign in successfully.

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Screenshots / Recordings

Before	After
(Duplicate Home, Dashboard, Leaderboard, and Contact)	(Clean, single list of 4 links)

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Checklist

• Linked the related issue above
• Self-reviewed my own diff
• No unnecessary console.log, debug code, or commented-out blocks
• npm run lint passes locally
• No TypeScript errors (npm run type-check)
• Added or updated tests where applicable
• Updated documentation / comments if behavior changed

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Accessibility (UI changes only)

• Keyboard navigation works correctly (the <button> respects focus-visible)
• Color contrast meets WCAG AA standard
• ARIA labels / roles added where needed
• Tested on mobile / responsive layout

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Additional Context

N/A

[github-actions]

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