GHSA-3cr3-8m4c-fpxw: Docling: METS-GBS archive member limit enforced after full member enumeration (memory exhaustion during format detection)

When docling detects the input format of a gzip-compressed tar archive (METS-GBS), and later when the METS-GBS backend opens it, it calls tarfile.TarFile.getmembers(). That builds the full member list in memory before the max_member_count limit is checked. A small archive with a very large number of empty members therefore makes docling allocate memory in proportion to the member count, and the limit has no effect.