feat: add GitHub-style notification center

[Sravya0509]

Description

Implemented a GitHub-style Notification Center feature.

Changes Made

• Added a new Notification Center component
• Integrated the notification center into the Topbar
• Added unread notification badge support
• Added notification dropdown UI
• Added actions for marking notifications as read and marking all notifications as read
• Improved user interaction and responsive behavior

Testing

• Verified the changes locally
• Confirmed the component integration with the Topbar

Notes

• The feature implementation is complete.
• Any existing unrelated SSR/localStorage issues are outside the scope of this PR.

[github-actions]

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[nensii21]

attached videos and screenshots showing what changes have been made also some CI jobs are failing update it.