feat: Add unread status indicator to notifications

[rozita-hasani]

#70 Implement notifications

Description

Implement basic notification service

Changes

• Implement notification system with unread status and UI panel
• Add notification bell, panel UI, and unread status tracking
• Implement notification service with API integration and UI updates
• Implement create, update and delete notification trigger

Checklist

• Code adheres to the project’s back-end guidelines.
• Unit tests cover new functionality.
• Integration tests are added or updated.
• Exception handling is implemented consistently.
• Logging is added for critical operations.
• Database migrations (if applicable) are included and tested.
• API documentation is updated if necessary.
• Changes are reviewed for potential performance impacts.
• Security vulnerabilities are assessed and mitigated.
• Dependencies are updated or verified as compatible.
• Code is reviewed for readability and maintainability.
• Environment configurations (if any) are documented.
• Endpoints are tested for expected behavior.