- Refactored websocket output collection to restore completed events using fallback items and indexed payloads.
- Updated `CodexExecutorCompact` tests to ensure no injection of `image_generation` tools and maintain compact input order.
- Added new tests to validate sustained reasoning, proper output restoration, and compaction replay behavior.
- Improved logic to handle incremental response appends and preserved reasoning continuations.
- Enhanced test coverage for normalization, tool calls, and downstream payload restoration scenarios.
Closes: #4176