Function transition_allowed 

pub fn transition_allowed(
    from: LifecycleState,
    to: LifecycleState,
    stats: &SkillStats,
    now: DateTime<Utc>,
) -> bool

Returns true if the transition from from to to may be persisted right now. Even when next_state says a transition is warranted, this guard prevents:

• flap within MIN_DWELL_HOURS of the last transition
• downward transitions for pinned skills below their pinned tier
• hysteresis bounce around exact thresholds