tests(config-variations): Git schemes in repo URLs

[tony]

Fixes #49

In main repo URLs:

Main repo URLs require libvcs.url.git.GitURL support:

Scheme: user@domain.tld:org/repo.git
Example: git@github.com:tmux-python/tmuxp.git

For remote URLs, see #419

Note: The workaround is to prepend git+ssh://git@github.com:tmux-python/tmuxp.git

[codecov]

Codecov Report

Attention: Patch coverage is 78.94737% with 8 lines in your changes missing coverage. Please review.

Project coverage is 78.98%. Comparing base (34966a5) to head (530c10e).

Files with missing lines	Patch %	Lines
src/vcspull/url.py	77.77%	5 Missing and 3 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #426      +/-   ##
==========================================
- Coverage   78.98%   78.98%   -0.01%     
==========================================
  Files           8        9       +1     
  Lines         414      452      +38     
  Branches       85       94       +9     
==========================================
+ Hits          327      357      +30     
- Misses         52       57       +5     
- Partials       35       38       +3     

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[tony]

Closing — the feature is obsolete, fixed upstream in libvcs.

This PR added a url.py that monkeypatched libvcs's core-git-scp rule to make SSH-style user@host:path URLs detectable as explicit Git URLs. Its own doctest documented the problem as GitURL.is_valid('user@hostname:path/to/repo.git', is_explicit=True) == False.

On current libvcs that rule already ships is_explicit=True, so:

• GitURL.is_valid('user@hostname:path/to/repo.git', is_explicit=True) → True (no patch)
• vcspull.cli.sync.guess_vcs(url='user@hostname:path/to/repo.git') → 'git' on master, unpatched

Re-authoring would only add a no-op patch that mutates libvcs's global rule objects — fragile shared state for zero behavior change. SSH-style config URLs work today without it. Closing as superseded; if a regression guard is wanted, a small test asserting guess_vcs handles SSH-style URLs would be the way, independent of this branch.