develop github workflow for assessment process

[iantaylor-NOAA]

Note: there are currently 11 watchers of this repository. Remember that you can unwatch if you get tired of all the notifications that will surely increase in frequency in the months ahead. Or stay tuned in if you want to watch the yellowtail assessment show.

In 2021 Kelli Johnson introduced me to the idea of assessment repository as R package as described here: https://github.com/pfmc-assessments/lingcod?tab=readme-ov-file#overview. We should decide whether to do that for Yellowtail Rockfish in 2025 and think about other repository organization and workflow questions.

I found the R package approach useful for petrale in 2023 (see https://github.com/pfmc-assessments/petrale/tree/main?tab=readme-ov-file#compiling-the-document). One of the big benefits I saw was that you can create helper functions in an R directory that are automatically loaded by devtools::load_all(). However, with the planned move from sa4ss to asar for the assessment report there may be fewer helper functions needed.