CVE-2026-58441: Gitea: SSRF in restore-repo via unsanitized pull_request.yml Head.CloneURL

Gitea’s restore-repo CLI command restores a repository from a dump directory/archive. When parsing pull_request.yml from that dump, the Head.CloneURL field is used to add a git remote and fetch from it with no validation, because the safety check that’s supposed to guard it (CheckAndEnsureSafePR) is called with an empty commonCloneBaseURL, which silently disables it. This lets a malicious dump make the Gitea server execute git fetch against an attacker-chosen URL (SSRF), or disclose a local git repository via file://. This is a different root cause from the recently fixed path-traversal issue in the same command (#38215), which patched DownloadURL/PatchURL but not Head.CloneURL.