Add Admin page with Role based access

[MinavKaria]

Roles:

1. Admin to add users
2. Notes contributor
3. Notes admin wrt every year and branch for reviewing and merging

[manognya-kundarapu]

Can you please assign this issue to me as part of GSSOC25? @MinavKaria

[MinavKaria]

@manognya-kundarapu before this you'll need to add database integration

Start with #98 first

[ojha13291]

@MinavKaria if it is not assigned can you assign me ?

[MinavKaria]

@ojha13291 before this db integration is required

For that #98 should be completed first

[ojha13291]

@MinavKaria but you have pending pr for #98 issue, review and merge it so that i can work on this issue

[MinavKaria]

@ojha13291 That PR is done by a AI agent, I want someone to refer it and test it, and send a PR accordingly