How to import a proto file that imports other proto files

Suppose I have a `file1.proto` and it imports `file2.proto` at other path, `file2.proto` imports `file3.proto` at anther path. And many other imports. How can I import `file1.proto` and use methods inside it with dotnet-grpc tools?

Thanks.

Start with the dotnet-grpc tool documentation and use the described file1.proto, file2.proto, and file3.proto import chain as the reproduction. Clarify the supported setup for importing nested proto files and document the required paths and expected result.

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