Feature/dashboard charts UI redesign

[khushalkks]

Description

This PR replaces the default, outdated visual elements of the dashboard with two premium, interactive status and priority doughnut charts. It also fully revamps the design system by integrating Outfit typography, high-contrast Slate color variables, and polished glassmorphic styling with smooth 3D hover-lift transitions.

Changes Made

• Installed recharts to enable visually stunning and reactive data visualization.
• Created TaskChart.jsx displaying two side-by-side doughnut charts: Task Status (with centered completion percentage) and Task Priority (with Red/Blue/Green theme).
• Upgraded the entire visual layout of Dashboard.jsx to stretch across full-screen width with optimized grid columns.
• Replaced hardcoded teal color variables in Navbar.jsx with standard Tailwind slate and indigo classes for unified theme aesthetics.
• Redesigned index.css by importing the modern Outfit geometric font, adding a premium radial mesh background gradient, and setting up smooth shadow-lift transitions for cards.
• Polished InsightCard.jsx to properly align within the new responsive grids.

Screenshots (if UI changes)

Checklist

• I have read CONTRIBUTING.md
• My branch follows the naming convention
• I have tested this locally
• Linting passes (npm run lint in frontend/)
• No unrelated files were modified
• Screenshots are attached (if UI change)
• [ ]

[khushalkks]

Hi Maintainers,

Thank you for reviewing the PR. Please let me know if any changes or improvements are required from my side. I would be happy to update them.

[khushalkks]

PLS CHECK