[Feature Request] Support SSH URL format for downloading Claude plugins from internal GitLab

Bug Description
Please support for ssh url format when downloading a claude plugin being in the internal gitlab.

Environment Info

• Platform: darwin
• Terminal: iTerm.app
• Version: 2.1.187
• Feedback ID: 2f1f99d3-13e2-4d90-8505-bf78a1c2844a

Repro

Input

claude plugin marketplace add ssh://git@git.example.com:2201/some-path/internal-marketplace.git

Errors

✘ Invalid marketplace source format. Try: owner/repo, https://..., or ./path