[Task] Create CI/CD unit tests and integration tests

[JasonBarahan]

Task

Create unit and integration tests. Key areas of concern include:

• QR code regeneration
• QR code functionality in various cases (normal/newly refreshed/replaced but has not expired yet)
• Login
• Data integrity and availability
• user registration
• Stamps being displayed in user view as it should

Steps

• Implement tests. Let's cook!

[JasonBarahan]

These are just preliminary ideas - we can modify them to be more precise as we head down the development timeline