src/orchestrator/events.ts — run event bus + wire contract

Purpose

run() never calls a Logger directly: every log.X(...) emits a RunEvent through busLogger onto an in-process bus; the terminal renderer is just the always-on subscriber. An embedder attaches as another subscriber with no orchestrator change (@vzn/vx-mcp reads run history, not the bus). A bus handed in through RunOptions.bus keeps the embedder’s subscribers across runs; what each run adds to it, the run removes on its way out (orchestrator.md).

Public surface

• createEventBus() — synchronous, order-preserving fan-out.
• busLogger(bus) — Logger-shaped facade that emits events.
• terminalSubscriber(sink) — drives a concrete renderer.
• WireEvent + toWireEvent — the SERIALIZABLE projection (task ids instead of node back-refs; bigint ns as decimal strings), and wireForwarder(send), the subscriber that pushes every event through it. Exported for an embedder that carries a run across a process boundary; nothing in core consumes it (the telemetry records in telemetry.ts are a separate projection).
• TaskView / OutcomeView with projectNode / projectOutcome — the wire’s task and outcome shapes; RunStartInfo is the run’s.
• The outcome vocabulary, one copy for every surface: outcomeWord (success / restored-local / restored-remote / up-to-date / failed / skipped / aborted), outcomeLabel (the word with a failure’s reason or a skip’s blocker), failedLabel, skippedLabel and skippedReason. The frame footer, the run report, the terminal summary and --summarize all read these.

Invariants

• Fan-out is synchronous, so terminal output is byte-identical to the pre-bus direct-call era.
• Raw TaskOutcomes are NOT serializable (bigint + graph back-refs); anything crossing a process boundary goes through toWireEvent.