Function resolve_routine 

pub fn resolve_routine(kind: BreakKind, s: &Settings) -> ResolvedRoutine

Resolve the guided routine for a break of kind from the user’s per-kind settings: "" → none, a routine id → that routine, "random" → the engine picks one from the filtered pool. Unknown ids and the Sleep kind resolve to an empty routine. A single random_index call is made so steps and pacing always come from the same pick.