Fix footer dead links and update GitHub icon

[Arya125-droid]

Description

This PR cleans up the dead links in the global Footer to prevent the UX bug where clicking a # link frustratingly scrolls users back to the top of the page. It updates the GitHub icon to point to the live repository and safely removes dead social/page links per the issue's out-of-scope constraints.

Type of Change

• 🐛 Bug fix (non-breaking change which fixes an issue)
• ✨ New feature (non-breaking change which adds functionality)
• 💥 Breaking change (fix or feature that would cause existing functionality to not work as expected)
• 📚 Documentation update
• 🔧 Refactoring (no functional changes)
• ⚡ Performance improvement
• 🧪 Test addition or update

Related Issues

Closes #617

Changes Made

• GitHub Link Updated: Pointed the GitHub icon's href to https://github.com/LabsCrypt/flowfi and added target="_blank" rel="noopener noreferrer" for security.
• Twitter Link Removed: Removed the Twitter icon completely since no official handle exists yet.
• Dead Sections Removed: Safely removed the dead text entries for the Product, Resources, and Legal sections (Privacy, Terms, Cookies) from Footer.tsx to prevent dead clicks.

Testing

Test Coverage

• Unit tests added/updated
• Integration tests added/updated
• Manual testing performed

Test Steps

1. Navigate to any page and scroll down to the global Footer.
2. Click the GitHub icon and verify it opens the official repository in a new browser tab.
3. Verify that the Twitter icon and the previous text lists (Product, Resources, Privacy, Terms, Cookies) are no longer visible.
4. Verify no remaining links in the footer trigger a scroll-to-top behavior.

Checklist

• My code follows the project's style guidelines
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published
• I have checked for breaking changes and documented them if applicable

Additional Notes

Designing new documentation pages was explicitly marked as out-of-scope for this issue, so the dead links were removed entirely rather than stubbed out.