Bugfix for MCMC with encoding

[odunbar]

Purpose

Content

• Fixed MCMC log posterior calculation bug for multiple observations
• Tightened up test framework, and made it more robust to priors etc. (with transformations) and learn_noise=false in GP. as they appeared to often overfit
• added more figures and diagnostics to help with testing
• added better ND->1D testing

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• I have read and checked the items on the review checklist.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.98%. Comparing base (101d3f6) to head (32005e5).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #378      +/-   ##
==========================================
+ Coverage   93.61%   93.98%   +0.37%     
==========================================
  Files          10       10              
  Lines        1628     1630       +2     
==========================================
+ Hits         1524     1532       +8     
+ Misses        104       98       -6     

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[ArneBouillon]

LGTM

[odunbar]

Merging on test pass and review