Add gRPC client and server sample for ASP.NET Core 10

[timdeschryver]

Fixes #36698

• Moved current docs to v9 "archive"
• Updated the sample to .NET 10
• Updated the screenshots and references to .NET / VS 26

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Internal previews

📄 File	🔗 Preview link
aspnetcore/tutorials/grpc/grpc-start.md	Tutorial: Create a gRPC client and server in ASP.NET Core
aspnetcore/tutorials/grpc/grpc-start/sample/sample10/readme.md	aspnetcore/tutorials/grpc/grpc-start/sample/sample10/readme

[wadepickett]

Found a few minor items to fix first. Otherwise, looks great!

[wadepickett]

@timdeschryver, great work and really appreciated!