Add ability to exclude certain paths from checks

[SRGDamia1]

I would like to exclude some folders from library structure checks - essentially the same folders from my .gitignore. In my case, I'm getting "ERROR: Sketch(es) found outside examples and extras folders" because I have a local .pio folder with local libraries in it and another local .history folder for a VSCode extension.

Additional context

Additional requests

• Allow disabling LS005 (symlink) and LS007 (.exe) if the file is gitignored #894

[dankeboy36]

From #894 (comment):

if the matching files are listed in .gitignore

My current thinking is that it would be better to use a dedicated configuration file rather than sharing .gitignore. This is what I see done by other tools, for example

• https://eslint.org/docs/latest/use/configure/ignore
• https://prettier.io/docs/ignore

The dedicated file could serve as a general purpose container for any other user configurations we later choose to implement.

This would also give us the option of using modern approaches for the configuration (e.g., regular expressions).

I agree that a general "exclude paths" feature makes sense and would cover this use case (and many others) more cleanly.

Tools like ESLint and Prettier perform both the "work" (formatting and writing files) and the validation. In contrast, Arduino Lint only handles validation. The actual "work" of packaging and excluding files for an Arduino library is done by Git. This makes .gitignore the single source of truth for what will end up in the published library.

For example, if .arduinolintignore excludes a folder that contains an .exe file, Git might still include it in the release (if it's not also in .gitignore). Arduino Lint would pass, but users might receive a library with an unexpected executable, which could be problematic.

By the way, both ESLint and Prettier automatically respect .gitignore, even when they support their own ignore files. I may be misunderstanding how the Library Manager works internally, but I wanted to share why I lean toward .gitignore as the cleaner approach in this case.

That said, I'm happy to go with whichever direction you think is best, whether that's a dedicated ignore file or .gitignore. I'd love to have this feature and would be happy to help implement it if there's a decision on how to proceed. Let me know what you think!