Add a test suite for critical functionalities

[code-geek]

Description

Currently we have a very limited test suite which makes it difficult to have confidence in our deployments. We want to add a test suit incrementally, starting with our most critical functionaties.

Implementation Considerations

• Use pytest
• Identify critical functions
• Write comprehensive tests

Deliverable

• A working test suite that can be invoked from local
• Add test suite to CI/CD; before merging a PR, all tests should pass
• Coverage report of tests; aim to have this at or greater than 90% at all times.

Dependencies

No response