Adding descriptors for various sections of the docs

[ForgottenProgramme]

PR Checklist:

• make all edits to the docs in the src directory, not in docs or in the html files
• note any issues closed by this PR with closing keywords
• put any other relevant information below

[ForgottenProgramme]

@viniciusdc

[jaimergp]

I like this idea but it'll look different in Docusaurus. I'll link back to this work when that happens.