GraphRunStream

Drive the run to completion and return the final state.

Drive the run to completion, then return whether it was interrupted.

Drive the run to completion, then return interrupt payloads.

Stop the run early.

Closes the mux and marks the stream exhausted. The graph iterator is dropped; any in-flight nodes see the closure on their next yield point. Idempotent.

Iterate multiple projections round-robin, yielding (name, item).

Each turn advances one projection's cursor; when a cursor's buffer is empty, pulling from it drives the pump once, which fans out to every subscribed projection log. Projections whose items aren't consumed on this turn sit in their own buffers only until the next turn reaches them, bounding memory by the skew between projection rates rather than letting any single log grow to the full run length.

Projections are exhausted independently; a projection that finishes early drops out of the rotation while others continue. The overall iterator ends once all named projections are done.