Register brain data layer as LLM-callable tools in Pi SDK agent
sessions. Agents can now query/create/update projects, tasks,
missions, and conversations through tool calls.
- 7 brain tools: list/get projects, list/create/update tasks,
list missions, list conversations
- Tools registered via customTools in createAgentSession()
- Uses TypeBox schemas for parameter validation
Closes#22
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>