CorpusSort='stat' fails on neovim 0.9.1

[Mike Lee Williams]

Looks like 1ad8312 depends on neovim/neovim#22846 when it calls vim.uv.fs_stat. At the time of writing, lib.uv requires an unreleased build of neovim, and is not available in the latest official release, which is 0.9.1.

The README warns that "Corpus requires a recent version of Neovim", so I hesitate to call this an issue, and I will absolutely not be offended if you close this immediately, but it's an easy fix if you choose to maintain support for the latest official neovim release.

[Greg Hurrell]

Thanks for the heads up. I agree that the compatibility fallback is simple enough to implement so I'll do that.