Project & Application System (Dhruv)

Title: Implement Project and Project Application Models
Models to create:
-Project
-prof → FK to User (Professor)
-title
-description
-is_formal_sop
-status (Open / Closed)
-Project Application
-project → FK
-student → FK to User
-status (Interested / Shortlisted / Accepted)

Also:
Add relationships properly
Run migrations