Add A New Slide

## We Need More Slides
Grab another octocat and create a new slide from scratch.
If you need help, check out the Appendix in the training manual.

Start by reviewing the repository’s existing slide structure and the Appendix in the training manual. Identify where a new slide belongs and how existing slides are formatted; done means an additional octocat-based slide is added consistently with the project’s materials.

索引モデルが issue の本文から書いたものです。