CVE-2026-53552: Goploy: Cross-namespace IDOR and RCE via body-supplied row id in project and project_file handlers

Project.AddFile, Project.EditFile, Project.RemoveFile, and Project.Edit in cmd/server/api/project/handler.go accept a project or project-file row id from the JSON body and act on it without checking that the project belongs to the caller’s namespace. The corresponding model.ProjectFile.GetData and model.Project.GetData queries filter only by row id. A user holding the manager role (or any role that includes the FileSync / EditProject permission) in their own namespace can read, write, or delete files in any project across the install, and can rewrite any project’s git remote URL by submitting the foreign id in the body. The git-URL primitive escalates to RCE on the next deploy because Edit runs git remote set-url on the project’s working tree.