Public PKCE client on kc.coulomb.social with local and production redirect
URIs. Add register-keycape-client.sh, document env, and harden public-client
token exchange (no secret). Authorize probe verified registered vs reject.
Django scaffold aligned with the business delivery lane: tenant-keyed
Member model without passwords, identity app as sole OIDC/session
boundary, dev-claims login, authenticated /app/ shell, ADR-0001, and
tests. T01/T02/T05/T06 done; OIDC registration, real user-engine HTTP,
flex-auth, and packaging remain open.
