Reconstruct the current plan for an agent instance.
Replays plan-related log events (PLAN_CREATED, PLAN_UPDATED, STEP_STARTED, STEP_COMPLETED) to build the current plan state.
Returns: Instance plan with ordered steps and their statuses.
Raises: NotFoundError: If instance not found or belongs to another organization.
Successful Response
Reconstructed plan for an agent instance, derived from log events.
Attributes: instance_id: Agent instance this plan belongs to. steps: Ordered list of plan steps with current status. created_at: When the plan was first created. updated_at: When the plan was last modified.