docs: modernize README with 2025 best practices

- Add compelling introduction with clear value proposition
- Document use cases with real-world scenarios
- Expand installation options (binary, Docker, source)
- Add comprehensive MCP host configuration guides for:
  - VS Code with GitHub Copilot (1.101+)
  - Claude Desktop
  - Cursor IDE
  - Windsurf IDE
  - Generic MCP clients
- Include side-by-side binary vs Docker configurations
- Document both MCP tools (get_action_parameters and get_readme)
- Add parameter tables for clarity
- Include example workflows and natural language queries
- Add troubleshooting sections for each platform
- Improve manual testing documentation (explain MCP server behavior)
- Add development, testing, and contribution sections
- Include security best practices
- Add support channels and related projects

Follows structure and best practices from GitHub's official MCP server README.

Co-authored-by: AI Assistant <ai@cursor.com>

Author: philprime