epic: Move Docs back into Cortex repo

[dan-menlo]

Goal

• Continue.dev and others are able to refer to @docs
• We are a small team and Docs should be part of Eng work

[hiento09]

Added @urmauur here to update all the website links, i.e. when user visits jan.ai/cortex/homebrew, adn clicks the "edit this page"

[gabrielle-ong]

Thanks @hiento09 and @urmauur! Marking as complete