no-gold-plating

Keep Claude Fable 5 / 5.1 changes minimal — no unrequested refactors, abstractions, defensive code, feature creep, or test files out of proportion to the change. Use in code review, bug fixes, and any coding session where diffs come back bigger than the ask, with extra helpers, error handling, "while I was here" cleanup, or more committed tests than the change warrants. Particularly important at high and xhigh…