Fix Navbar Navigation Indicator & Alignment Issues

[ArshiBansal]

Description

This PR resolves multiple UI inconsistencies in the navigation bar to improve visual hierarchy, alignment, and overall user experience.

Changes Made

• Removed the navbar-wide progress underline that stretched across the navigation container.
• Updated the active navigation state to highlight only the currently selected menu item.
• Improved spacing between navigation links for better readability and balance.
• Standardized utility action button dimensions (Search, Bookmark, GitHub, etc.) for consistent sizing and alignment.
• Refined navbar layout spacing to create a more balanced desktop experience.
• Improved streak badge icon/text alignment.
• Enhanced active navigation styling with a pill-based indicator for clearer page context.
• Preserved existing mobile navigation behavior and responsiveness.

Result

The navbar now maintains a cleaner visual hierarchy, provides a more intuitive active-page indicator, and ensures consistent spacing and alignment across navigation links and utility actions.

Fixes #577

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)
• This change requires a documentation update

How Has This Been Tested?

Local Testing

Verified the following scenarios locally:

1. Active navigation state correctly highlights only the current page.
2. Navigation links maintain consistent spacing and alignment.
3. Utility icons render with uniform dimensions and positioning.
4. Navbar layout remains visually balanced across desktop screen sizes.
5. Mobile navigation drawer functionality remains unaffected.
6. Search, bookmark, theme toggle, notifications, and profile/login actions continue to function as expected.
7. Maintenance mode behavior remains unchanged.

• Local testing
• Vercel Preview Deployment

Checklist

• My code follows the style guidelines of this project
• 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 or errors
• I have checked that the "DevPath India" branding remains intact

[Aditya948351]

Thanks for fixing the Navbar alignment! Just a heads-up, this might overlap with another PR (#596) that also modifies the Navbar styling. I'll review both and figure out the best way to merge.