edited UI and created navbar component

[Shazzz135]

This pull request introduces a new global navigation bar to the application and standardizes page layouts to accommodate it. The main changes include adding a reusable Navbar component, updating all major pages to include top padding so content is not hidden behind the fixed navbar, and removing redundant navigation code from individual pages. Additionally, the dashboards and authentication pages are updated for consistency.

Navigation and Layout Updates:

• Added a new Navbar component (frontend/src/components/ui/Navbar.tsx) that provides a consistent navigation bar across all pages, including authentication-aware buttons and logout functionality.
• Inserted the Navbar into the main app layout by updating App.tsx so it appears on every page. [1] [2]
• Removed old navigation bar code from the Welcome page and refactored its layout and marketing content for a more modern landing experience.

Page Layout and Spacing Adjustments:

• Added pt-20 (padding-top) to the main containers of all major pages (e.g., Home, dashboards, schedule, availability, password reset) to ensure content appears below the fixed navbar. [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11]

Dashboard and Auth Page Consistency:

• Updated all dashboard pages (Admin, Candidate, Interviewer) to remove their individual logout logic and header button, relying on the global navbar for authentication actions. [1] [2] [3]

These changes collectively improve navigation consistency, modernize the landing experience, and ensure a uniform layout throughout the app.

[Flapjacck]

LGTM