No timeout on subprocess.run git calls

[lcarva]

Description

In verify.py:30-38, the git clone and git checkout subprocess calls have no timeout parameter. A malicious or unresponsive repository URL could hang the process indefinitely.

This also applies to the CLI's diff command where the user provides the --repo URL directly.

Suggested fix

Add a reasonable timeout to both subprocess.run calls, e.g.:

subprocess.run(
    ["git", "clone", "--", repo_url, str(dest)],
    check=True,
    capture_output=True,
    timeout=300,  # 5 minutes
)