Limited file write via unchecked docs path

Path traversal in Arc53 DocsGPT before 0.8.1 allows remote attackers to write two attacker-selected files through the check_docs endpoint. The endpoint concatenates the unauthenticated docs POST value into a local vectors path and a raw.githubusercontent.com URL, then saves retrieved index.faiss and index.pkl content without validating the resolved source or destination. A reachable backend API and attacker-controlled files at the selected GitHub location are required, and the write is limited to those two filenames beneath the traversed path.