Create a Custom View for OAuth Login and User Creation [93-4]

[mehalyna]

• Task: Implement a custom API view to handle OAuth-based login.
• Steps:
  1. Add logic to authenticate users using Google/GitHub OAuth.
  2. Check if the user exists; if not, create a new user.
  3. Assign the authenticated user a JWT token.
• Deliverable: OAuth login view implemented.

---

US #93