[Bug]: Replace standard `<a>` tags with Next.js `<Link>` components for internal navigation

[ArshVermaGit]

Description

The application currently uses standard HTML <a> tags for internal routing across several pages instead of the Next.js <Link> component.
This is a Next.js anti-pattern that breaks Single Page Application (SPA) routing. When users click these links, the browser performs a full page reload rather than a fast, client-side navigation. This degrades performance, increases server load, and removes the seamless SPA feel of the dashboard.

Affected Files

Based on ESLint (@next/next/no-html-link-for-pages) warnings, the following files are known to contain this issue:

• src/app/compare/[users]/page.tsx
• src/app/dashboard/settings/page.tsx
• src/app/u/[username]/page.tsx
• src/components/landing/LandingPage.tsx
  (Note: There may be other files affected. A project-wide search for <a> tags pointing to internal routes should be conducted).

Expected Behavior

Internal navigation should be instantaneous without triggering a full browser refresh, preserving client-side state and offering a smooth, optimized user experience.

Steps to Reproduce

1. Navigate to the Landing Page, Dashboard Settings, or a Public Profile.
2. Click on an internal link (e.g., navigating back to the home page / or to an authentication endpoint like /api/auth/signin/github/).
3. Observe the browser tab reloading the entire page instead of a smooth SPA transition.

Proposed Solution

1. Identify all instances of standard <a> tags used for internal routes (e.g., routes starting with /).
2. Import the Next.js Link component: import Link from 'next/link';
3. Replace the <a> tags with <Link> components, keeping the href attribute intact.
4. Run npm run lint to verify that the no-html-link-for-pages ESLint warnings have been resolved.