Make `lint-staged` cover more files

We can make the `lint-staged` work in the root folder to cover more files, e.g. `/docs/*.md`, etc.

Start by locating the root lint-staged configuration and reviewing its current file patterns; compare them with repository files such as /docs/*.md. Done means the root configuration covers the intended additional files and the lint-staged check runs successfully.

Written by the indexing model from the issue text.