From population instruction to collected entity

A hook describes an entity or list population instruction and subscribes to the graph. The engine deduplicates concurrent identical work, records subscriber tokens, returns current data, and revalidates stale subscribed entries in the background. Focus and reconnect mark subscribed data stale; unsubscribed data is not revalidated merely because it exists.

Stale-while-revalidate keeps the last usable projection visible while a service refreshes canonical data. Suspense may coordinate the initial absence of data, but it does not become the state owner. Garbage collection removes entities after the configured retention boundary when no lists, relations, or active subscribers require them.

Tune staleTime, retry, and GC from observed application behavior. A shorter timer is not automatically more correct: it increases I/O and can hide an incomplete realtime contract.