[Bug] Agent Teams Planning mode documentation inaccurate for agent behavior

Bug Description
Agent Teams Planning mode not correctly described for agents

Environment Info

• Platform: darwin
• Terminal: iTerm.app
• Version: 2.1.138
• Feedback ID: eb07ca19-1f50-4ac6-bfcd-412b07b571f4

Errors
Claude Code agents are unable to figure out how to use the Planning mode of Agent Teams. Based on only tool descriptions, the teammates attempted to use SendMessage to send the plan as a plan_approval_request type, which is not a valid type for SendMessage. After investigating the Claude Code JS, we were able to find that the correct flow is for the teammate to be spawned in Plan mode, and the ExitPlanMode call triggers the notification to the team lead.