test(pipeline): commit InDesign sample fixtures exercised in CI — closes epic #61

[PAMulligan]

Closes the InDesign-to-WordPress epic (#61). All sub-issues (#62–#66) are already merged to main; this PR resolves the one remaining epic acceptance criterion:

Sample fixtures (.idml and exported PDF) are committed under tests/fixtures/indesign/ and exercised in CI.

Approach — fixtures as code, not blobs

Per the pipeline's standing convention (and the parser/smoke tests), the canonical sample document — a two-spread Spring Brochure (text-heavy cover + image-heavy hero with master-spread footer chrome) — is a readable spec materialized into both input formats on demand, rather than committed binaries:

File	Purpose
tests/fixtures/indesign/brochure.mjs	The spec + buildBrochureIdml() / buildBrochurePdf()
tests/fixtures/indesign/emit.mjs	CLI: writes brochure.idml + brochure.pdf to disk
tests/fixtures/indesign/fixtures.test.mjs	End-to-end test (runs in CI)
tests/fixtures/indesign/README.md	Documents the fixtures + no-blobs rationale

What's exercised in CI

fixtures.test.mjs runs the full pipeline (parse → map tokens → generate) for both formats and asserts each yields:

• a schema-valid theme.json (version 3, populated palette + typography scale)
• one block pattern per spread under the InDesign Imports category
• both report files (.md + .json)

Plus a source-agnostic check that the .idml and PDF import the same logical brochure (same spread/pattern count). Wired into pipeline-tests.yml (test-indesign-pkg job) with tests/fixtures/indesign/** added to the path filter.

Verification

pnpm --filter @flavian/pipeline test          → 100 passing
node --test tests/fixtures/indesign/fixtures.test.mjs → 3 passing (IDML + PDF + equivalence)
node scripts/indesign-fse/smoke-test.mjs      → ✓ valid theme

Also verified the emitted files run through the real CLI end-to-end:
node tests/fixtures/indesign/emit.mjs → flavian pipeline indesign brochure.idml / brochure.pdf → valid themes.

Epic acceptance criteria — all met

• .idml → working FSE theme (≥1 pattern/spread + theme.json)
• PDF → equivalent output with documented fidelity caveats
• Patterns render in the Site Editor on the happy path
• indesign-to-wordpress agent in README + .claude/agents/
• flavian pipeline indesign <input> documented in docs/
• Sample fixtures committed under tests/fixtures/indesign/ and exercised in CI ← this PR

Once merged, #61 can be closed.

🤖 Generated with Claude Code