supersedes #1167, does basically the same but with globbing logic moved into its own library as suggested by maintainers

this is the followup pr mentioned in #1163. i've opened this mainly to get feedback from the maintainers on the best way to implement this. i can port the globbing code into its own package if needed, even though this isn't that much code

according to globby's readme the only exclusive features it has (that are relevant in this case) are negated patterns and directory expansion, which this pr both covers

the issues reported in 6.2.1 were all related to either me forgetting to handle negated patterns in entry or not knowing directory expansion was meant to be done. if there is any more globby-exclusive functionality missing let me know and i'll add it

i'd be happy to test any possible edge cases in the logic and add new tests

ref: #1163 (comment)