## 1. Backend - SSH Existence Check

- [ ] 1.1 Add `git ls-remote` preflight to repository creation in `git_repositories.py`
- [ ] 1.2 Build SSH clone URL from `owner` and `repo` for `git.commumedia.org`
- [ ] 1.3 Return a clear error when the repository is missing or inaccessible

## 2. Frontend - Structured Clone Form

- [ ] 2.1 Update `RepositoryCreateDialog` clone mode to accept `owner` and `repo`
- [ ] 2.2 Keep advanced full-URL paste flow and blank repository fallback
- [ ] 2.3 Reuse the shared dialog from repository settings and repositories page

## 3. Validation and Docs

- [ ] 3.1 Update repository docs to explain SSH-only owner/repo input
- [ ] 3.2 Add tests for success, missing repo, and URL fallback behavior

## 4. Quality Gates

- [ ] 4.1 Run backend and frontend targeted tests
- [ ] 4.2 Run frontend typecheck and lint where applicable
- [ ] 4.3 Commit and push changes