fix(eslint): support running in git submodule

[LeoMcA]

also add some jsdoc type hinting

Trying to commit locally I was getting this error:

Oops! Something went wrong! :(

ESLint: 8.48.0

Error: Cannot read config file: /workspace/yari/.eslintrc.cjs
Error: ENOTDIR: not a directory, lstat '/workspace/yari/.git/info/exclude'

I've been running yari from a git submodule as an easier way of transferring my dev environment state between devices. I'm not sure it's a setup we want to explicitly support, but it should fail more gracefully than an error message and no commit.

[fiji-flo]

one nit