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 inspecting the existing slides in the repository and consult the Appendix in the training manual for the expected structure. Done means adding a new slide from scratch with another octocat, matching the project's existing slide format.

索引モデルが issue の本文から書いたものです。