9e8b9ec470
Flip the naming default from `flat` (slug.md) to `stable_per_directory_4digit` and seed `counter_dirs` with the four document-producing directories (specs, plans, design contracts, design models) so the counter policy is effective out of the box. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>