fix: recursive directory filtering in ShouldExclude

[crackcomm]

Ensure ignore rule bar/ matches directories by appending /. Addresses issue where bar/ didn't catch directories. After this change, both bar and bar/ rules filter out the bar directory and its contents.

Note: This is required because git would skip empty directories and use full paths relative to repo.
I'm not sure how much I could break the API but it's still just using file names as opposed to full relative paths for filtering which is not ideal.

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[hacdias]

@crackcomm just to understand: you're saying the current implementation is not fully compatible with https://git-scm.com/docs/gitignore, correct? If so, do you mind fixing the tests (adding the .IsDir method to the mock), as well as adding a regression test to ensure that this is working as expected?

[crackcomm]

@crackcomm just to understand: you're saying the current implementation is not fully compatible with https://git-scm.com/docs/gitignore, correct?

Yes, this PR fixes:

frotz/ matches frotz and a/frotz that is a directory (all paths are relative from the .gitignore file)

Nevertheless even after this change it's not fully compatible. To be fully compatible, the paths have to be matched against a relative path, right now it's just a file name.

[crackcomm]

@hacdias I can add the function to the mock, no problem but could you please guide me where to add the test?

I would also want to add another change (not sure if separate PR or should I change this one): do NOT add the hidden files when they match ignore rules even if filter.IncludeHidden is true. Do you think that is a reasonable change?

[hacdias]

@crackcomm as for adding a test, I think filter_test.go is the place to go.

Do you think that is a reasonable change?

I think so. To me, that sounds like something that should've already been happening. If it is explicitly ignored as per the file, IncludeHidden should not override it.

For me you can include it with this PR, but please keep the commits separate just in case.

[lidel]

Triage notes:

• Rebased, but CI fails
• TestFileFilter seems to fail on CI, needs to be updated (and cI needs to be green)
• We need a PR against Kubo that confirms these sharness tests that use filtering via --ignore* param in ipfs add pass

@crackcomm are you able to address the above?