Cache checked and mapped regex patterns

[jg-rp]

This PR adds an LRU cache and uses it to cache regex patterns for the match and search function extensions.

Previously we relied on the re module's internal cache. But since we now check patterns against I-Regexp (if it's installed) and map patterns from I-Regexp to Python re compatible patterns, we need our own cache.

Both jsonpath.function_extensions.Match and jsonpath.function_extensions.Search now also accept additional constructor arguments:

• cache_capacity: The size of the regular expression cache.
• debug: When True, raise an exception when regex pattern compilation fails. The default - as required by RFC 9535 - is False, which silently ignores bad patterns.
• thread_safe: When True, use a ThreadSafeLRUCache instead of an instance of LRUCache.