The report kept a placed document's LINKED FILES and FONTS inside its parent's list. Each document
now gets its own sections, the packaged one first and unchanged (no Document: line), then each
placed document's, headed by its file. Drops a debug_assert and an unneeded mut, runs rustfmt, and
documents the nested packaging in docs/mcp.md and the ROADMAP.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>