70de19815e
- Added checkpoint and rewind tools to create context checkpoints before exploratory work and rewind to replace exploration messages with concise reports. - Added checkpoint.enabled setting to control availability of checkpoint and rewind tools in agent sessions. - Added getCheckpointState() and setCheckpointState() methods to agent session API for checkpoint state management. - Implemented checkpoint state tracking with message count, entry ID, and timestamp to enable context cost optimization during investigations.