Under the hood
Background thread classifier no longer produces its experimental "turn brief" summaries
What
The background classifier that generates recaps of project threads has had its "turn brief" summarization removed. It no longer computes this summary, no longer logs a turnBrief field on the tengu_bg_classify event, and no longer emits the separate turn_brief telemetry event.
Why
This rolls back a feature that had been added but was not yet fully wired up, cleaning up code and telemetry that were not being put to use.