persona.txt:
- DELEGATION: 'default to spawning, not to doing inline' — stronger default,
  clearer triggers, explicit when-not-to-spawn rules
- PLANNING: ties automatic planning phase to mandatory todo(op='set') as first
  tool call; reconciles pre-loop plan with in-loop execution discipline
- SCRATCHPAD: new section — when to write, section naming conventions,
  mandatory read before final answer

Profiles (secretary, server_admin, smart_home):
- All three now share the same 18-tool set (each file independent)
- planning_enabled=True on all three
- scratchpad and web_search added to smart_home
- System prompts updated with scratchpad/todo execution discipline sections

agent.py run_ephemeral:
- Each subagent gets a unique session ID (subagent_<uuid>) for scratchpad
  isolation — parallel or sequential subagents no longer share working notes

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>