Support a friendlier format

[orhun]

Editing JSON for the slides is not optimal. Instead, we can consider:

• Changing the format to something else (e.g. TOML)
• Using proportions of the screen instead of raw coordinates
• Having a slide editor TUI of some sort :D

Tell me what you think :)

[t-h2o]

Hi !

What about creating a converter, Markdown to JSON?
to create simple slides