Authorization: Add [Authorize] flag to restricted endpoints #96

What and why

Proper authorization is critical for ensuring that only authenticated users can access protected resources and perform sensitive operations. Without it, unauthorized users could potentially read, modify, or delete data that should be secured.

Currently, very few endpoints that should be restricted are actually protected by authorization. This creates a security vulnerability and weakens trust in the system.

Suggestion

Add the [Authorize] attribute to all endpoints except:

• POST /login/ -> Login endpoint
• POST /users/ -> Public registration end-point
• POST /validation/ -> Validate password end-point
• GET /validation/ -> Validate end-point

Progress

• Repair tests
• CohortEndpoints.cs [WIP, see BACKEND - Implement Cohort structure #91]
• LogEndpoints.cs
• PostEndpoints.cs
• SecureApi.cs
• UserEndpoints.cs
• ValidationEndpoints.cs

Benefits

• Prevents unauthorized access to sensitive operations.
• Strengthens the overall security of the API.
• Establishes a clear, consistent standard for authorization across the back-end.