Refactor Python and Orthanc Dockerfiles

[jeremyestein]

Description

Fixes #588 :

A cut down version of #400 , with just the Dockerfile de-duping. If we decide #400 is too risky to merge now, we can at least merge this one and do the rest of #400 later. The advantage is it enables further work on the Dockerfiles, such as switching to uv.

Type of change

Please delete options accordingly to the description.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Suggested Checklist

• I have performed a self-review of my own code.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• I have commented my code, particularly in hard-to-understand areas.
• I have passed on my local host device. (see further details at the CONTRIBUTING document)
• Make sure your branch is up-to-date with main branch. See CONTRIBUTING for a general example to syncronise your branch with the main branch.
• I have requested review to this PR.
• I have addressed and marked as resolved all the review comments in my PR.
• Finally, I have selected squash and merge

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 87.24%. Comparing base (208e74c) to head (b1aa5f8).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #583   +/-   ##
=======================================
  Coverage   87.24%   87.24%           
=======================================
  Files          76       76           
  Lines        3380     3380           
=======================================
  Hits         2949     2949           
  Misses        431      431           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[p-j-smith]

looking really nice - just a question around downloading the DICOM spec for Orthanc Anon

[stefpiatek]

Looks good, will leave it to you and Paul to work out the best way to have the python spec downloaded and cached