History cleanup task list

This is a simple super issue collecting various smaller tasks that might be good first issues to tackle.  They could be converted into individual issues as well to track completion via PRs as well.

```[tasklist]
### Tasks
- [ ] Propagate use of `patch_area_div_site_area` introduced in #1252
- [ ] https://github.com/NGEET/fates/issues/1379
```
