Fix Client methods without result generated by testing/codegen

[tchssk]

No description provided.

[Copilot]

Pull Request Overview

This PR fixes client method generation for services without result types in the testing/codegen package. The changes ensure that methods without results properly handle endpoint calls by discarding the return value and returning only errors.

• Adds test data for services with and without result types to validate the generation
• Updates client method templates to properly handle methods without results
• Creates comprehensive tests to verify correct client generation

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
testing/codegen/testdata/dsls.go	Adds DSL definitions for services with and without result types
testing/codegen/testdata/code.go	Adds expected generated code for both service types
testing/codegen/templates/client_methods.go.tpl	Fixes template to properly handle methods without results
testing/codegen/clients_test.go	Adds comprehensive tests for client generation

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[raphael]

This is great, thank you! (and apologies for the delay)