CCISS results interpretation vignette

Create a vignette (or multiple) walking through how to interpret CCISS results, what is driving those trends, how to think about them, caveats, etc.
Using one example species and area, for example western redcedar expansion into the SBS

No file, test, or entry point is named. Start by locating existing CCISS vignettes and reviewing the workflow and subprojects, then identify the inputs and outputs for a western redcedar expansion example in the SBS. Done means a vignette explains how to interpret the results, their drivers, relevant caveats, and how to think about the observed trends.

Written by the indexing model from the issue text.