chore: Update README.md file according to DevEx guidelines

[Copilot]

Updated the README.md documentation to follow internal DevEx guidelines for better developer experience and consistency across repositories.

Changes Made

Structure Improvements:

• Reorganized content into proper sections: Description, Setup Instructions, API Usage, Automation Setup, Running Tests, and Troubleshooting
• Added clear section hierarchy with appropriate markdown headers
• Improved overall document flow and readability

New Content Added:

• Development Setup section with clear installation instructions for internal developers
• API Usage section with properly formatted endpoint documentation, parameters, and examples
• Troubleshooting section addressing common issues developers might encounter
• Running Tests section explaining the current testing approach

Content Enhancements:

• Enhanced the existing Slack integration setup with better formatting and clearer steps
• Improved API examples with proper parameter documentation
• Better organized automation setup guidance
• Added deployment guidance for serverless functions

Quality Improvements:

• Used proper markdown formatting with language-tagged code blocks
• Ensured consistent internal documentation tone
• Preserved all valuable existing content while improving organization
• Removed redundant information and improved clarity

The README now provides a comprehensive guide for internal developers while maintaining all the practical setup information that was previously available.

Fixes #11.

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