ai_grants_unified UNIONED the assistant grants.json with the legacy
settings/ai_permissions.json on every read. On archi-dev-box legacy held
all-ten and grants.json held four, so the Settings UI and the AIUI frame
saw every category ON while the assistant refused six — and no UI toggle
could fix it, because both write paths existed but only ai.permissions.set
synced both files. Now: an existing grants.json answers alone; the legacy
file is consulted only when no grants file exists (pre-unification
upgrade), and that read migrates forward and persists the authority.
assistant.grants-set now also rewrites the legacy file in step. Regression
tests: authority is not widened by legacy; migration folds forward once.
Co-Authored-By: Claude <noreply@anthropic.com>
