Streaming Modes

Two streaming modes, picked with StreamingMode:

from pyrula.workflows.stream.kinds import StreamingMode

safe (the default) buffers output and publishes it in one shot when the step finishes. live publishes chunks as they arrive.

Reach for safe when a consumer should see a result exactly once. Reach for live when latency matters more and consumers can handle a chunk being restarted or overwritten on a boundary.