CVE-2026-33678: Vikjuna: IDOR in Task Attachment ReadOne Allows Cross-Project File Access and Deletion

TaskAttachment.ReadOne() queries attachments by ID only (WHERE id = ?), ignoring the task ID from the URL path. The permission check in CanRead() validates access to the task specified in the URL, but ReadOne() loads a different attachment that may belong to a task in another project. This allows any authenticated user to download or delete any attachment in the system by providing their own accessible task ID with a target attachment ID. Attachment IDs are sequential integers, making enumeration trivial.