Add "dropout" option to the scheduling

[mcoughlin]

30% of the time will be modeled as downtime, and so we need an option that corresponds to "losing" those observations.

[codecov]

Codecov Report

Merging #73 (564ddce) into main (25ea652) will decrease coverage by 0.53%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main      #73      +/-   ##
==========================================
- Coverage   30.36%   29.83%   -0.54%     
==========================================
  Files          35       35              
  Lines        1683     1713      +30     
==========================================
  Hits          511      511              
- Misses       1172     1202      +30     

Impacted Files	Coverage Δ
dorado/scheduling/scripts/animate_survey.py	5.59% <0.00%> (ø)
dorado/scheduling/scripts/simsurvey.py	7.12% <0.00%> (-0.70%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 25ea652...564ddce. Read the comment docs.

[mcoughlin]

Unit tests pass. Merging.