Add translate-book to Document Processing section.

Claude Code skill that translates entire books (PDF/DOCX/EPUB) into any language using parallel sub-agents.

• Parallel subagents — 8 concurrent translators per batch, each with isolated context
• Resumable — chunk-level resume; already-translated chunks are skipped on re-run
• Manifest validation — SHA-256 hash tracking prevents stale or corrupt outputs
• Multi-format output — HTML (with floating TOC), DOCX, EPUB, PDF

Repository: https://github.com/deusyu/translate-book (400+ stars)