Release v2.1.0: Improve overflow handling and add comprehensive tests

- Replace silent infinity returns with explicit OverflowException
- Add overflow detection during calculations
- Expand test coverage with edge cases
- Update documentation for breaking changes
- Bump version to 2.1.0

Release v2.0.0 - Major Update

## New Features
- Complex number support integrated with expression parser
- Enhanced polynomial factoring (quadratic, cubic, special forms)
- New ODE solver methods: RungeKutta2 and Adams-Bashforth
- Rational function integration with partial fractions
- Extended symbolic integration capabilities

## Improvements
- Removed inline comments for cleaner, more professional code
- Better error handling and validation
- Performance optimizations in precision calculations
- Extended test coverage (131 tests passing)

## Added Classes
- ComplexExpression for complex number handling
- PolynomialFactoring for advanced factoring
- SymbolicIntegration for symbolic calculus
- Matrix and MatrixOperations for linear algebra
- Plotter for ASCII function visualization

Release v1.1.0 - Arbitrary Precision Support

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