Onboarding: Clone URL uses HTTPS which fails for push

[styltsou]

During the onboarding process, the clone command provided uses an HTTPS URL (e.g., https://github.com/org/docs.git). When users try to push changes, it fails with an authentication error:

fatal: could not read Username for 'https://github.com': No such device or address

This is likely because:

1. GitHub has deprecated HTTPS password authentication
2. Users may not have configured Git credentials for HTTPS
3. SSH would work but isn't offered as an option

Steps to reproduce:

1. Complete Mintlify onboarding with a new docs repository
2. Copy the clone URL provided (HTTPS format)
3. Make a change and try to git push
4. Push fails with authentication error

Suggested fix:

• Use SSH URLs by default (e.g., git@github.com:org/docs.git)
• Or detect user's Git configuration and prefer their preferred protocol
• Or show a warning during onboarding about authentication setup