- 401 without/with a bad token (incl. WWW-Authenticate: Bearer), 200 with a
valid one, driven through the ASGI app in-process.
- configure_http refuses to start when the token is unset or blank.
- FAMILIAR_HTTP_* config defaults and overrides; http_token() strip/empty.
- HTTP write default disabled by default, env still wins, stdio stays enabled.
- parse_callback (URL / bare code / empty) and the manual_login exchange flow.