Under the hood
Internal rework of how chat history renders speaker labels and message rows
What
The internal code that computes speaker-label continuation state (whether consecutive messages from the same speaker are grouped together), reply boundaries, and message row rendering in the chat history view was restructured, including a new memoized rendering call. No new user-facing capability was identified.
Why
This appears to be an internal refactor of chat history rendering with no described change in what users see or can do.