* implement GitHub OAuth
* fmt and clippy
* add secrets for GitHub App in workflow
* fix env vars
* use device flow for login instead of callback for better security, add email and username to posthog analytics
* cleanup
* add user details to sentry context
* fixes after rebase
* feedback fixes
* do not allow to press esc to hide github popup
* use oauth app to get user token with full repo access
* use PAT token as a backup for creating PRs
* update github signin box text
* update sign in box styling
* fmt
---------
Co-authored-by: Gabriel Gordon-Hall <ggordonhall@gmail.com>