Spectrum fitting for activation foils

[RemDelaporteMathurin]

This PR reimplements what was proposed by @cdunn314 in #47

It adds new objects:

• CheckSource : is composed of a Nuclide, an activity date, and an activity
• Detector: has a channel_nb, holds the events (time and energies) as well as the count times (real and live)
• Measurement : is composed of several Detector, and has a start and stop time. Can also be used for background measurements.
• CheckSourceMeasurement : is a child class of Measurement, and has a CheckSource attached to it. It is useful to compute the detection efficiency of detectors

I also moved almost everything to compass.py to avoid circular imports

I've also tried to test as much as possible. Tests can probably be simplified in some cases but I'm happy to refactor tests in a future PR.

Next steps (in future PRs) will hopefully close the analysis:

• Making an object for activation foil measurements (inheriting from Measurement)
• Compute the activity of an activation foil
• Integrate with the existing capabilities to work out the neutron fluence based on an irradiation schedule

[codecov]

Codecov Report

❌ Patch coverage is 89.52381% with 22 lines in your changes missing coverage. Please review.
✅ Project coverage is 84.74%. Comparing base (0775c8e) to head (c61e420).
⚠️ Report is 101 commits behind head on main.

Files with missing lines	Patch %	Lines
...lbox/neutron_detection/activation_foils/compass.py	88.48%	22 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #71      +/-   ##
==========================================
+ Coverage   84.49%   84.74%   +0.25%     
==========================================
  Files          18       18              
  Lines        1193     1331     +138     
==========================================
+ Hits         1008     1128     +120     
- Misses        185      203      +18     

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[RemDelaporteMathurin]

please ignore this file it's just for showing some of the usage for now

[cdunn314]

I didn't test the code but I did look through most of it.