## Why
Persisted transcripts rendered tool calls individually and displayed reasoning differently from live replay. Enabling raw reasoning also replaced the summary instead of retaining it.
## What changed
- Group computer activity and compatible exploration commands across intervening reasoning, retaining details for the expanded transcript. Respect visible content, command failure boundaries, and turn boundaries.
- Separate paginated history at every turn boundary before filtering hidden items, while adding completion metadata only for successful turns.
- Keep persisted reasoning out of the compact display, preserve hyperlinks in detailed rendering, and append enabled raw reasoning to the summary. Preserve standalone reasoning Markdown in transcript exports.
- Add helpers to rejoin activity groups and attach reasoning across page boundaries using persisted item identities and turn adjacency.
## Testing
Add regression coverage for reasoning replay parity, computer groups split across history pages, turn boundaries, and grouped terminal input. Update export and raw-reasoning tests to verify retained summaries and Markdown.
GitOrigin-RevId: a716db571440f891cc2c6894ae93fbe0e149aed4
Eric Traut
f43faf132d