Mirror ERP5's own document-naming convention (e.g.
`P-WOELFEL-Presentation.Roadmap.Beirat.2026.04-001-de.pdf`) when no
`--output` is given, falling back to a slug of the title for documents
without a reference set.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>