Interface RunnerRuntimeOptions

The host Durable Object's single pubsub identity from do-runner/pubsub.ts, threaded here by init() alongside storage and the ledger so a host that configures it reaches the runtime with no host change: every DO subclass already returns init()'s runtime from build(), and nothing else in the isolate can hand this object a pubsub.

PASSED TO CORE at the two workflow.createRun({ runId, pubsub }) sites in start()/resume() — the only place core accepts one; the pubsub getter still exposes the held identity so an agent runner sharing this isolate takes THIS instance rather than building a second feed. Absent ⇒ undefined ⇒ core defaults a fresh emitter per run ⇒ byte-identical to before this seam existed.

Consulted on every start/resume — see RequestContextProvider.

Per-run resume ledger backing RunSummary.resumeCount / RunLeg.resumeCount. Default: in-memory. The DO shell adopts a ctx.storage-backed ledger via adoptDefaultResumeLedger() so the ordinal survives eviction — an explicit ledger here wins over that adoption.