[moetemp]

What changed?

This PR pins sdk-streams s15 daeb5fc2 and syncs the WIT and proto copies with the crate.

The WIT copy in scripts/_wit is now the crate's crates/streams/nexus/stream-service.wit, whose @nexus.doc lines fit 100 columns. The extension proto drops the buffered writer path: Publish, FlushWriter, batch_interval, max_buffered_records and the stream_buffer_full reason. The bindings are regenerated, and only their docstrings change.

On the Python side, StreamBufferFullError goes, since no call can raise it now. The test fake loses its Publish and FlushWriter branches. The facade already used only WriteRecords and CloseWriter, and BatchOptions was already gone.

Why?

The awaited publish writes with one WriteRecords call, and BufferedPublisher batches in Python, so the crate's interval flush has no user. The crate is the source of the WIT now, so each SDK copies one file.

How did you test it?

pytest tests/contrib/streams on the memory Store and on a scratch redis-server, against the stock dev server. test_vectors matches the crate's protos at the new pin. poe lint passes.

• Unit Tests
• Staging
• End to End Tests

[moetemp]

Closing as stale. This layer is folded into the v5 tip, #365, and the upstream review uses a fresh series instead. Plan: https://www.notion.so/4048fc567738814990b7c796ac28fe3f