- Add ExecutePatrolStream method to chat.Service for patrol-specific execution
- Create chat_service_adapter.go to bridge chat.Service to ai.ChatServiceProvider
- Remove standalone patrol.go and patrol_test.go from chat package
- Add PatrolRequest/PatrolResponse types to chat service
- Add context injection for recent message context
This allows patrol to use an isolated agentic loop with its own system prompt
while leveraging the common chat infrastructure.