Implement robust Arkane LevelOfTheory matching with year support

Update the Arkane statmech adapter to match ARC levels against the RMG database using normalized method and basis strings. This adds support for the recently introduced `year` attribute and handles 4-digit year suffixes in database entries, prioritizing exact year matches or the latest available version.

The matching logic now ignores hyphens, spaces, and casing, and provides improved warning messages that list available years when a specific level of theory is not found in the database.

Author: calvinp0