Enhance trigonometric functions documentation with comprehensive law examples and notebook studies

[AronT-TLV]

This PR enhances the trigonometric functions documentation and adds comprehensive examples of trigonometric laws with practical notebook implementations.

Documentation Enhancements

• Cosine Law Extensions: Added documentation showing how the Cosine Law extends the Pythagorean theorem
• Special Triangle Cases: Documented behavior for isosceles and equilateral triangles
• Sine Law Comprehensive Coverage: Added alternative forms and complete documentation of the Sine Law
• SSA Triangle Analysis: Documented Side-Side-Angle scenarios including impossible triangle cases

Practical Examples

• Notebook Implementation: Added comprehensive worked examples in Basics.ipynb
• Cosine Law Examples: SSS (Side-Side-Side) and SAS (Side-Angle-Side) scenarios
• Sine Law Examples: AAS (Angle-Angle-Side) and SSA (Side-Side-Angle) scenarios
• Error Handling: Demonstrated proper error handling for impossible triangle calculations
• Educational Clarity: Clear explanations of when triangles are mathematically impossible

Technical Improvements

• Julia Best Practices: Used try-catch blocks for graceful error handling in domain errors
• Mathematical Accuracy: Proper handling of inverse trigonometric functions with domain restrictions
• Symbol Usage: Updated copilot instructions for consistent mathematical symbol usage

Key Files Modified

• docs/src/Trigonometry/02 Trigonometric Functions.md: Enhanced with comprehensive law documentation
• notebooks/Basics.ipynb: Added practical examples with error handling
• .github/copilot-instructions.md: Updated mathematical symbol guidelines

🎯 Educational Impact

• Complete coverage of fundamental trigonometric laws
• Practical examples with step-by-step calculations
• Proper error handling demonstrations
• Clear explanations of mathematical limitations
• Enhanced learning experience with interactive notebook examples

This enhancement provides a comprehensive foundation for trigonometric studies with both theoretical documentation and practical computational examples.