[bug] Not rendered diagram under phase 16 communication protocols

## Where - Phase / lesson: Phase 16 / Communication protocols - URL : https://aiengineeringfromscratch.com/lesson.html?path=phases/16-multi-agent-and-swarms/03-communication-protocols#step-3-a2a-task-lifecycle ## What's wrong Diagram could not be rendered. ## Reproduce 1. Visit the [page](https://aiengineeringfromscratch.com/lesson.html?path=phases/16-multi-agent-and-swarms/03-communication-protocols#step-3-a2a-task-lifecycle) ## Environment - OS: Windows - Browser: Google Chrome - In production web ## Screenshot or logs <img width="1898" height="872" alt="Image" src="https://github.com/user-attachments/assets/c0d5e230-d428-4fda-82ad-49e6200504a1" />