Revise MCP agent documentation for clarity and detail

[AClerbois]

Updated expertise and guidelines for MCP tools, prompts, and resources. Enhanced best practices for attributes and resource management.

Pull Request Checklist

• I have read and followed the CONTRIBUTING.md guidelines.
• My contribution adds a new instruction, prompt, or chat mode file in the correct directory.
• The file follows the required naming convention.
• The content is clearly structured and follows the example format.
• I have tested my instructions, prompt, or chat mode with GitHub Copilot.
• I have run npm start and verified that README.md is up to date.

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Description

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Type of Contribution

• New instruction file.
• New prompt file.
• New chat mode file.
• New collection file.
• Update to existing instruction, prompt, chat mode, or collection.
• Other (please specify):

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Additional Notes

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By submitting this pull request, I confirm that my contribution abides by the Code of Conduct and will be licensed under the MIT License.

[Copilot]

Pull request overview

This PR enhances the C# MCP Expert agent documentation to provide comprehensive guidance on all three major MCP server capabilities: tools, prompts, and resources. The updates reflect a more complete understanding of the Model Context Protocol and provide detailed best practices for implementing each component type.

Key Changes:

• Extended expertise section to explicitly include prompt and resource design patterns
• Expanded attribute lists to cover [McpServerPromptType], [McpServerPrompt], [McpServerResourceType], and [McpServerResource]
• Added three dedicated best practices subsections with specific implementation guidance for tools, prompts, and resources