Add comprehensive documentation to README.md

[Copilot]

Enhanced the README.md with comprehensive documentation to improve developer experience and library adoption. The documentation now provides complete coverage of all features, APIs, and usage patterns.

What's Added

Professional Structure:

• Added status badges for build, Go report card, GoDoc, and Go version
• Complete table of contents with nested navigation
• Clear section hierarchy for better readability

Installation & Setup:

• Step-by-step installation instructions for the core library
• Installation commands for all supported resource type packages
• Development setup guide for contributors

Enhanced API Documentation:

• Complete API reference for all public types (Runner, Program, Resource, ResourceConfig)
• Detailed function documentation with parameters, return values, and examples
• Comprehensive configuration options documentation with defaults
• Code examples demonstrating every major function

Practical Guidance:

• Advanced usage patterns for multiple resource types
• Context cancellation and timeout handling examples
• Dynamic resource registration patterns
• Error handling strategies with specific error types
• Production-ready best practices and performance considerations
• Comprehensive troubleshooting guide with common issues and solutions

Developer Resources:

• Contributing guidelines with step-by-step instructions for adding new resource types
• Issue reporting template
• Development workflow documentation

Examples Added

The documentation now includes practical examples for:

• Basic resource availability testing
• Multiple resource type usage
• Context timeout and cancellation
• Dynamic resource registration
• Error handling patterns
• Performance optimization techniques
• Debugging and troubleshooting workflows

This comprehensive documentation transforms the README from a basic quick-start guide into a complete reference that supports both new users getting started and experienced developers implementing advanced use cases.

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💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.