Added AspNetCoreClient sample, Extended the existing AspNetCoreSseServer sample

[sabbadino]

Motivation and Context

The samples folder contains a AspNetCoreSseServer, but not a AspNetCoreClient

How Has This Been Tested?

No changes in the library, just adding a sample.
The AspNetCoreSseServer has been modified to add a new MCP tool

Breaking Changes

None

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• [X ] New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• [ X] I have read the MCP Documentation
• [X ] My code follows the repository's style guidelines
• [ X] New and existing tests pass locally
• [X ] I have added appropriate error handling
• [ X] I have added or updated documentation as needed

Additional context

The AspNetCoreClient acceptts sampling.
The new WeatherMcpTool added to AspNetCoreSseServer asks for sampling (if the requiresPostProcessing is true)
Added AddHttpLogging in the AspNetCoreSseServer to see request and response payload