Create workspace from PR

You can now create a workspace directly from a PR, existing branch, or Linear issue using ⌘⇧N.

Improvements

• Added a more noticeable onboarding sequence for new users
• Close the new workspace popup when pressing Escape
• Add a Learn More link under Auto-Merge in settings

Fixes

• Fix file picker not loading large file trees
• Fix Linear auth not redirecting users to the main app on success
• Fix attachments panel positioning