fix: redirect user based on role after login instead of hardcoding admin dashboard

[pericharlabindhumadhavi-data]

Closes #240

What was the problem?

After successful authentication, both regular login and Google login flows redirected users to:

/admin/dashboard

This redirect was hardcoded and ignored the role information returned by the authentication response. As a result, non-admin users were incorrectly routed to the admin dashboard.

How was it solved?

• Removed hardcoded navigation logic.
• Added role-based redirect handling using the roles returned by the API.
• Ensured users are redirected to the appropriate destination based on their assigned role.

Impact

• Prevents unauthorized navigation to admin views.
• Improves user experience after login.
• Aligns application routing with role-based access expectations.

Checklist

• Removed hardcoded dashboard redirects.
• Added role-aware navigation logic.
• Tested login flow with different user roles.
• Followed CONTRIBUTING.md guidelines.