[GHSA] GHSA-mj63-m3rc-8ppr (medium) — league/commonmark: Denial of service via deeply nested XML output

GHSA-mj63-m3rc-8ppr Severity: medium CVE: None

league/commonmark: Denial of service via deeply nested XML output

### Impact

`XmlRenderer` pretty-prints XML by emitting depth-proportional indentation whitespace for **every** opening and closing tag. For a tree of depth n, the indentation alone sums to **O(n²)** bytes of output (and corresponding memory), reachable through `MarkdownToXmlConverter