Convert test-matrix from single container to DAG with two parallel branches:
- test-glibc: Full test suite including OCR (tesseract available on Debian)
- test-musl: Production binary feature set (no OCR, unavailable on Alpine)
Musl leg configuration:
- Image: ghcr.io/cross-rs/x86_64-unknown-linux-musl:main
- Test: cross test --release --target x86_64-unknown-linux-musl --features default,serve,decrypt
- Output: JUnit XML artifact (test-results-musl.xml)
- Test threads: 4 (parallel execution)
Also updates:
- .nextest.toml: Add JUnit XML output settings to profile.ci
- Cross.toml: Add cross configuration for musl target
Bead: pdftract-5gtcj
Plan section: Phase 0.3
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>