Book → Repo Sync Review (2025-12-20)

Reviewed against git rev-parse HEAD at the time of writing, plus local working tree changes.

Checks Run

mdbook build book
mdbook test book
cargo build -p doc-snippets
Verified book/src/SUMMARY.md covers all pages in book/src/ (no orphaned pages)
Verified all scripts/... paths referenced from the book exist
Compared NOMOS_* environment variables used in scripts/, testing-framework/, and examples/ vs. book/src/environment-variables.md

book/src/environment-variables.md was not a complete reference: it missed multiple NOMOS_* variables used by the repo (scripts + framework). Added the missing variables and corrected a misleading note about RUST_LOG vs node logging.
book/src/running-examples.md “Quick Smoke Matrix” section didn’t reflect current scripts/run/run-test-matrix.sh flags. Added the commonly used options and clarified the relationship to NOMOS_SKIP_IMAGE_BUILD.
book/src/part-iv.md existed but was not in book/src/SUMMARY.md. Removed it so the rendered book doesn’t silently diverge from the filesystem.
mdbook test book was failing because:
- Many Rust examples were written as ```rust (doctested by default) but depend on workspace crates; they aren’t standalone doctest snippets.
- Several unlabeled code blocks (e.g. tree/log output) were treated as Rust by rustdoc.
- Updated code fences to ```rust,ignore for non-standalone Rust examples and to ```text for non-Rust output blocks so mdbook test book succeeds.

All pages under book/src/ currently included by book/src/SUMMARY.md: