Intercept tool calls to webfetch at github.com

[diegohb]

This should be intercepted and replaced with deepwiki call:

1. WebFetch https://github.com/dotnet/aspire/blob/main/src/Aspire.Hosting.Yarp/YarpBuilderExtensions.cs
2. WebFetch https://raw.githubusercontent.com/microsoft/aspire/main/src/Aspire.Hosting.Yarp/YarpResourceExtensions.cs