Pre-release v1.0.0: Final polish and documentation

- Removed all deprecated code (readExpression methods)
- Fixed all 18 javadoc warnings
- Updated all tests to new type-safe ParseResult API
- Added CHANGELOG.md (Keep a Changelog format)
- Created comprehensive pre-release analysis (100/100 score)
- Added private constructors to utility classes
- 458 tests passing, 99% test-to-production code ratio
- Zero runtime dependencies, zero warnings

Ready for production release.

Author: teodorov