Add comprehensive test suite for DirectExtractionEngine and dual-track
integration. All 65 tests pass covering text extraction, structure
preservation, routing logic, and backward compatibility.
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Co-Authored-By: Claude <noreply@anthropic.com>
- Create test directory structure for backend
- Add pytest fixtures for test files (PDF, images, Office docs)
- Add 20 unit tests covering:
- PDF type detection (editable, scanned, mixed)
- Image file detection (PNG, JPG)
- Office document detection (DOCX)
- Text file detection
- Edge cases (file not found, unknown types)
- Batch processing and statistics
- Mark tasks 1.1.4 and 1.3.5 as completed in tasks.md
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
