DOC: suggest and/or implement improvements to our documentation

Currently our documentation is a bit austere:
https://pdfly.readthedocs.io/en/latest/

It's built using Sphinx

It's functional, but not really attractive.

How do you think we could improve it?

There are some first random ideas:

• adopt a more attractive Sphinx theme?
• consider adopting some Sphinx extensions: https://sphinx-extensions.readthedocs.io/en/latest/ (or consider switching to mkdocs if Sphinx ecosystem is really too limited)
• add GIFs or terminal emulators (like https://github.com/Kibibit/command-lime or https://github.com/luisbraganca/fake-terminal-website) to showcase what pdfly can do?
• add an example of usage with uvx, on the homepage, in a "quickstart" section?

Do you have other ideas? 🙂

Would you like to implement some of them?

Review the current Sphinx documentation at https://pdfly.readthedocs.io/en/latest/ and compare the proposed theme, extension, terminal-demo, and uvx quickstart ideas. Before starting, turn the discussion into a specific improvement with an agreed scope; done should mean the selected documentation changes are implemented and the published site is more useful and attractive.