permanent property
Whether the registration persists across a non-forced LevitScope.reset.
LevitScope.dispose always calls LevitScope.reset with force: true,
so permanent dependencies do not survive disposed scopes (including
unmounted LScope widgets and typical widget-test tear-down). Prefer
permanent: true on root / long-lived scopes; on short-lived page scopes
it does not extend lifetime past widget unmount.
Implementation
final bool permanent;