Un-recurse wildcard matching [NFC]

[kripken]

Avoids deep recursion on long names.

Fixes #7981

[tlively]

Pushing two tasks at each step, one that still has the wildcard and another that doesn't, seems overly complicated and expensive.

1. I would expect us only to push data onto the stack at necessary branch points in the search, not at every character.
2. If we encounter a mismatch, we should just pop the stack to backtrack (or return false if the stack is empty). There should be no need for a separate results vector.

[kripken]

The push at the end of the loop is redundant with the pop, but to save that work would make the code more complex. And this is not performance-sensitive code.

Otherwise I don't quite follow your suggestions?

[tlively]

To illustrate what I mean (and to procrastinate on working on various slide decks) I went ahead and implemented what I had in mind: #7988. I'm happy to go with whichever approach seems simpler, though. (Maybe a hybrid approach would be simplest.)

[kripken]

Closing in favor of the other PR.