supabase_migrations registry row missing for migration 131 (PLUTO-437)

131-pluto-437-pacientes-identity-anchor.sql was applied via raw psql (not mcp__supabase__apply_migration), so no row exists in supabase_migrations.schema_migrations for it. Confirmed: SELECT version,name FROM supabase_migrations.schema_migrations ORDER BY version DESC LIMIT 5 shows 130 (PLUTO-669) as latest, nothing for 131. Reproducibility gap: a fresh restore replaying the registry would skip 131 and diverge from live schema. Fix: backfill a row for 131 matching apply_migration's format, OR establish a policy that raw-psql-applied DDL always gets a follow-up registry backfill step. Decide approach before closing.