Docs: Add Knowledge Base (FAQ & Support)

[birkjernstrom]

Mintlify is adding Knowledge Base as a feature which we want to use. However, in the meantime, we're getting a lot of common support questions which would be great to document vs. repeat one-off and gatekeep behind support.

So let's start simple with a dedicated knowledge base to add some FAQs as we go and then port it over to the Mintlify option once it becomes available. Since everything is Markdown based it should be fairly easy to port regardless of how they set it up.