Pytests for each step in the workflow and initial GitHub Actions setup.

[Sasha-Barisic]

Good morning @pchlap,

Hope you are well!

In this PR:

• I have added unit tests for each step in the sequential workflow. Some can be refined further once the code is modularised.
• I have also added the initial GitHub Actions workflow to trigger on each PR.

Discussion

While developing a unit test for the scan_file function in preprocess.py, I tested what happens when a non-DICOM file is provided (even though this is unlikely in practice). I expected the result to be None and the status to be "error", but instead I received result = None, status = "ok", and an error message.

I also tried with a random DICOM file from the test data and encountered the same result - the status was "ok" despite an error being raised during scanning.

Looking at the scan_file function, it seems the except block does not explicitly set the status to "error". Was this intentional - perhaps to keep files in quarantine regardless of scan success?

I have commented out the affected unit tests for now:

• test_scan_file_unsuccessful (ID007)
• test_scan_file_successful (ID008)
  in test_preprocess.py.

Also, no urgency to review - just when you have some time.

Thank you and enjoy your weekend!