Re-add RequestExecutorSetup.SchemaBuilder

[tobias-tengler]

I removed this in #8758, since there were no references and it felt like a really obscure option... Turns out we're using it in Nitro, so I'm re-adding it.

[Copilot]

Pull Request Overview

This PR re-adds the RequestExecutorSetup.SchemaBuilder property that was previously removed, as it's needed by the Nitro project. The change restores the ability to provide a custom schema builder while maintaining backward compatibility.

• Re-adds the SchemaBuilder property to RequestExecutorSetup
• Simplifies the SchemaBuilder constructor to use default options
• Updates the request executor creation logic to use the provided schema builder or create a new default one

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
SchemaBuilder.cs	Simplified constructor to use default schema options and removed internal overload
RequestExecutorManager.cs	Updated to use the schema builder from setup and moved schema options creation logic
SchemaRequestExecutorBuilderExtensions.cs	Enhanced options modification to work with both schema builder and option modifiers
RequestExecutorSetup.cs	Re-added the SchemaBuilder property and updated copy logic
RequestExecutorWarmupService.cs	Added local implementation of schema options creation method

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 0.00%. Comparing base (12bfd27) to head (4f96585).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@     Coverage Diff      @@
##   main   #8810   +/-   ##
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