[design] Add string.contains()?

Hi Chapel Users and Developers —

Currently, Chapel's strings support a .find() method that returns the position of a substring within a string, or -1 if it is not found. In Add support for string.contains()? · Issue #19119 · chapel-lang/chapel · GitHub, I've proposed that we also support a .contains() method that would simply return true or false if a string contained a given substring, to simplify cases where that's all that's needed, and to mirror .contains() methods on other types (ranges, domains, collections, etc.).

If you have concerns about this proposal, please add them to the issue. If you support it, please give it a thumbs-up.