The Hub launcher used an ephemeral /tmp profile deleted on exit, which
wiped the hub_manual_logout marker cookie. On reopen, /auto-login minted a
new session and logged the user straight back in without a password.
Use a persistent per-user profile under XDG_STATE_HOME and drop the
deletion trap so the logout marker survives close/reopen. Keep
--skip-origin-startup-dialog. Adds regression tests.