Adding ability to run diagnostic functions on individuals

[sschildhauer]

This pull request will add the ability to run diagnostic functions on individuals using "id" as an input. Apologies for all of the files changed and this relatively big PR -- the same small changes were made across many functions, so I felt it made sense to group it into one PR. A couple of details:

• The default is "newperson".
• You can produce results for multiple individuals at once.
• The results produce lists of lists. I know this is not ideal, but I felt that facetwrap would likely create too convoluted figures. Plus, the list design makes it easy to call a specific figure from the result. We can discuss alternatives.

[github-actions]

📖 https://ucd-serg.github.io/serodynamics/preview/pr121
Preview documentation for this PR (at commit d4ab703)

[codecov]

Codecov Report

❌ Patch coverage is 97.69231% with 3 lines in your changes missing coverage. Please review.
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
R/plot_jags_effectivedx.R	96.96%	1 Missing ⚠️
R/plot_jags_rhatdx.R	97.05%	1 Missing ⚠️
R/plot_jags_tracedx.R	96.87%	1 Missing ⚠️

Files with missing lines	Coverage Δ
R/add_jags_atts.R	100.00% <100.00%> (ø)
R/plot_jags_densitydx.R	100.00% <100.00%> (ø)
R/plot_jags_effectivedx.R	97.05% <96.96%> (+0.63%)	⬆️
R/plot_jags_rhatdx.R	97.22% <97.05%> (+0.67%)	⬆️
R/plot_jags_tracedx.R	97.05% <96.87%> (+0.63%)	⬆️

[sschildhauer]

Hi @Kwan-Jenny , I am having a hard time troubleshooting this one -- I think everything was passing when I first wrote the function but it doesn't seem to be now. Could you take a quick look? We can ask Ezra if we can't figure out the issue. Just as a heads up, when I run the tests on my local Rstudio they all pass. I have also run document() and it doesn't update anything. Thanks a bunch!

[sschildhauer]

@Kwan-Jenny, thank you for the review! I took most of your suggestions but by the way the function works was not able to combine a few, specifically the one where I combine the stratification and id filter together. Can you take another look when you get a chance? Thanks!