.Net Agents - Use compile time logging messages

[crickman]

Adopting this patterns is in alignment with SK practices and general best practices:

• https://learn.microsoft.com/en-us/dotnet/core/extensions/logger-message-generator
• https://github.com/microsoft/semantic-kernel/blob/main/dotnet/src/SemanticKernel.Abstractions/Functions/KernelFunctionLogMessages.cs