[FR]: Non-Git way to ignore directories

### What is the current behavior?

Excluding a directory requires either:

1. Using .gitattributes (e.g. somedir/** rules-lint-ignored=true)
2. Using a formatter-specific exclusion (e.g. prettier exclusion file).

This is documented [here](https://github.com/aspect-build/rules_lint/tree/d91ed507dc9b8bb9720426b8aa2fde1a0e0ba79c?tab=readme-ov-file#ignoring-files).

### Describe the feature

Please consider adding an exclusion mechanism that allows path-based exclusion but is not coupled to git, so that users of other VCS systems can apply the path-based exclusion system available with .gitattributes. For example, it could be a .rules_lint_exclusions file in the root that functions effectively the same as .gitattributes exclusions, just without any reference to git. This would significantly improve the usefulness of the rule set for non-git VCS users.

Start with the linked “Ignoring files” documentation and review how the existing .gitattributes exclusions are described. Define the behavior and format of a proposed .rules_lint_exclusions file for non-Git VCS users, including path matching and precedence, then document the agreed mechanism and add coverage for it.

Written by the indexing model from the issue text.