initialize

Creates a fresh agent for every vehicle and for the dispatcher, and activates them.

Fresh, not reused: a KSLProcess is a coroutine that runs once, so an agent cannot be restarted. And because these are created while the model is running, they are deliberately not in AgentModel.agents -- which is why the fleet is enumerated from vehicles and why the handle is assigned unconditionally rather than reused. A retained agent would carry the previous replication's mailbox, which nothing resets for a runtime agent.