Function simulate 

pub fn simulate(
    graph: &RegionGraph,
    route: &Route,
    config: &SimConfig,
) -> SimReport

Replay route over graph against the real residency engine and the drive model, and report deadline slack and misses.

Each tick the player’s region fixes the wanted list: the regions the graph says it needs at demand class, every other region within the lead radius at lead class with a deadline of its walk distance at the assumed speed. The engine steps once per tick; the drive model decides when each read lands.