Private per-leg, per-runtime or per-component storage. A component slot declares this chart's entry root: internal unregistered subcharts share it; every separately mounted declared root gets a fresh bank. Declare before entry. An already-captured frame never follows a later declaration, and mismatched component access refuses. Every new leg, including same-executor resume, starts with fresh component values. Keep this lifecycle strongly reachable: a slot alone does not retain its weak component port.
One-shot SAME token; setup refusal spends it. Save its checkpoint for FRESH recovery. A failed withRun body withdraws the offered continuation.