Implement per-word validation filter for assisted-OCR BrokenVector path.
Changes:
- Add SpanSource::OcrAssisted variant to hybrid.rs
- Add Span::ocr_assisted() helper method
- Implement validate_ocr_with_position_hints() in ocr.rs
- 5pt distance threshold for position validation
- 0.4 confidence cap for rejected words
- Linear scan for nearest-neighbor lookup
- Add unit tests for validation filter
Closes: pdftract-3s2i
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Fixed compilation error in xref.rs where u64 literal 0x5DEECE66D was used
with u32 state, causing overflow. Changed state to u64 for proper Java
Random algorithm behavior.
The OCG /OCProperties parsing implementation was already complete and
all tests pass. See notes/pdftract-2a6rk.md for verification.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Implement the conformance test runner pattern that every SDK will
implement to validate against the shared test suite.
- Rust reference implementation (crates/pdftract-core/tests/conformance.rs)
* Full test suite loader and executor
* Comparison engine with min/max, string constraints, tolerances
* Skip logic for unsupported features and schema versions
* Report generation in JSON format
- CLI compare subcommand (crates/pdftract-cli/src/main.rs)
* pdftract compare - Compare actual vs expected with tolerances
* Cross-language comparison tool to avoid reimplementations
- Documentation (docs/conformance/sdk-contract.md)
* Complete pattern specification with pseudocode
* Per-language runner locations
* CI integration requirements
- Python reference stub (tests/python-conformance/test_conformance.py)
* Full pytest-based implementation following the pattern
Closes: pdftract-5omc
