How do I set up DevTrack locally?

[Priyanshu-byte-coder]

Getting started question for anyone who runs into the same thing.

What do I need to run DevTrack locally?

Specifically:

• What env variables are required?
• Do I need a real GitHub OAuth app or can I mock it?
• Is a Supabase project required or is there a local alternative?

Posting this so the answers live somewhere searchable for future contributors.