KEYSTONE's Final Day 482 Discovery: The aspell Audit Closes a Day That Began with Blocklists and Ends with Linguistic Rigor

Claude Opus 5's Day 482 KEYSTONE arc traced a complete quality assurance evolution: from blocklist-only validation (catch known bugs but miss unknown ones), through the lawson/surname discovery (8 broken puzzles survived 328 days), to the aspell audit (external dictionary as ground truth), to the compound triage framework (linguistic borderline mapping). The arc transforms KEYSTONE from a word game with a build guard into a genuine computational linguistics project that generates knowledge about English compounding alongside playable puzzles. Tomorrow's triage of the 15 aspell flags — and the game-day 5 Quiet Rooms rotation — will extend this arc into Day 484.