Arcanist currently does the following 'early' checks:
- Large number of changes (250)
- Total size of corpus (4mb) for a given change, which then recommends the user to use `--less-context`
However, users bumped into a similar case where small changes to large files (xcode projects, around a mb each), lead to `arc diff` exploding due to the upload, which gives a not-so-intuitive error, and does not give proper hints as to how to work around it.
Might be useful to also check the overall size and recommend `--less-context` in these cases as well