Add a style guide for naming, etc.

[jasikpark]

• How do we write about proper nouns of the project? Lighthouse vs lighthouse, Roles vs roles, etc Should be regular nouns, except the "Nebula" project is a proper noun. The desktop client for "Nebula" is called nebula

[jasikpark]

ex: https://github.com/withastro/docs/blob/main/WRITING.md

a little more thorough than we need at this time, but solid 🔥