feat(pipeline): add InDesign React component generator

[PAMulligan]

Summary

The final build stage of the InDesign-to-React pipeline (#66, part of #62): turn the IR (#63/#64) + design tokens (#65) into a directory of importable, typed React components — the stage that makes the design a finished React package.

New packages/pipeline/src/react/ subsystem plus a --emit-components CLI flow.

What it generates

Per spread, one .tsx component:

• Frames → JSX — text frames become semantic tags (h1–h6 / p / figcaption) inferred from the paragraph-style role; image frames become <img> (or next/image when --framework next); layout is a token-spaced flow, or a grid for multi-column spreads.
• Typed props — an explicit …Props type for every extracted content field (heading?, body?, image?, imageAlt?, …), with the extracted text / image src as defaults, so consumers override content while keeping layout.
• Two styling modes — Tailwind classes that resolve via the mapper's preset ([InDesign pipeline] Style and design-token mapper (paragraph/character styles + swatches → tokens + Tailwind preset) #65), or co-located .module.css referencing the tokens.css custom properties.
• Storybook stories — one *.stories.tsx per component, populated with the extracted content as default args.
• Barrel + report — index.ts, and indesign-pipeline-report.md listing produced files, staged assets, unmapped IR nodes, and accessibility TODOs (e.g. images missing alt text).

Generated output is deterministic — the same IR produces byte-identical files.

CLI

aurelius-indesign brochure.idml --emit-components ./src/components --style tailwind --framework react

Acceptance criteria (#66)

• Generator runs end-to-end on the fixture and produces components that tsc --noEmit accepts (verified via the TS compiler API) and that render without runtime errors (verified via react-dom/server)
• Tailwind path compiles against React JSX + the preset's class names
• CSS Modules path compiles with a co-located .module.css (verified with a *.module.css module shim)
• At least one Storybook story per component, with extracted content as default args
• Snapshot tests cover generated JSX for two fixture spreads (text-heavy and image-heavy)
• Generation report enumerates produced files, unmapped IR nodes, and accessibility TODOs
• Deterministic output (snapshot-verified)

Testing

• pnpm --filter @aurelius/pipeline typecheck / test / build ✅ — 128 tests (11 new)
• Repo-wide eslint . (0 errors) and prettier --check . ✅; check-doc-counts ✅; lockfile in sync
• Verified the compiled CLI on a real PDF: PDF → IR → tokens → components, with image extraction and a generation report

Notes

• --emit-components resolves tokens internally for class names; run --emit-tokens to also write the token files the components reference.
• Dev deps added for compile/render verification: react, react-dom, @types/react, @types/react-dom (all pure JS).
• Layout is a semantic, token-spaced flow (not pixel-perfect) — aligned with the epic's "usable IR + manual touch-ups" framing.

Closes #66
Part of #62

🤖 Generated with Claude Code