6604ecb026
- feat: cross-user file access returns not-found instead of permission-denied - fix: repository delete now only affects active rows and returns ErrNotFound when no row changes; repeated deletes yield not-found - feat: parent directory operations (list, upload, create-dir, move) conceal ownership of other user's directories - test: update handler, service, repository, and integration tests to assert not-found behavior for cross-user and missing file operations