Fix output presentation and move highlighting to Rust

[maebli]

What changed

• restore the colored, semantically grouped Mermaid diagram output
• emit exactly one CSV data row per input frame, with records represented by namespaced columns
• remove the CSS behavior that doubled JSON, CSV, and XML line spacing and truncated the line-number gutter
• replace the documentation's npm/Shiki toolchain with a Rust syntect highlighter exported from the WASM package
• add a quote-aware Rust CSV tokenizer, semantic column colors, and audited WCAG AA light/dark palettes
• remove all repository npm manifests, lockfiles, generated npm highlighter assets, and npm CI steps
• regenerate the checked-in documentation WASM
• add the complete 0.4.1 changelog and version metadata

Root cause

The code viewer applied block layout and minimum height to Shiki's inline line spans while also retaining source newline separators. That rendered each logical line twice as tall and made a newline-counted gutter appear to stop early. CSV rendered one row per record, repeating frame fields, and the newer Mermaid renderer had dropped the previous semantic colors.

Validation

• cargo fmt --all -- --check
• cargo clippy --workspace --all-features --exclude pymbusparser -- -D warnings
• cargo clippy -p pymbusparser --all-features -- -D warnings
• cargo test --workspace --all-features --exclude pymbusparser
• wasm-pack test --headless --firefox (8 passed)
• Python binding 0.4.1 release build plus 7 unit tests
• final documentation WASM budget and npm-free contract tests
• Rust CLI smoke tests for one-row CSV and colored Mermaid output

No npm tooling, dependencies, manifests, or lockfiles remain in the repository.