pub(crate) fn lock_current_break<T>(m: &Mutex<T>) -> MutexGuard<'_, T>Expand description
Recover from poison rather than silently swallow or panic. If the
current_break mutex was poisoned by a panicking writer, we still
want to publish into the slot — losing the publish breaks tray
countdown + cold-mount overlay invariants. The inner data is
always valid (we never leave the slot in a half-written state
between locks), so taking it back is safe.