- test_change_password_revokes_other_sessions: verifies skip_token_hash
preserves current session while revoking all other refresh tokens
- test_enable_totp_revokes_other_sessions: verifies TOTP enrollment
revokes other sessions via skip_token_hash
- test_disable_totp_revokes_other_sessions: verifies TOTP disablement
revokes other sessions via skip_token_hash
- All three marked xfail(strict=False); currently xpassed (backend already complete)
- Plan 08-03 promotes these to strict passing tests
