Additive migration: nullable profiles.gender / chart_profiles.gender with a
female/male CHECK, owner-only via existing table RLS, column grants mirroring
the neighbouring birth columns (service_role for the account PATCH, no
admin_runtime). Account PATCH/GET, people POST/PUT/GET, subject resolution
and the consult route carry each person's own value; a people write only
touches gender when the key is sent. DB test runs in the gate's DB job.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017eEAG8HD3mm8gsKXgk8uU8
