Conditionally imports the samples only if its the root project

[jclyne]

When pulling this project into a composite project, via IncludeBuild, the samples are not necessary nor probably desired. They also cause issues as a transitive dependency

Motivation and Context

Improves the ability to pull the SDK into a composite build

How Has This Been Tested?

yes, tested locally in a composite build

Breaking Changes

N/A

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the MCP Documentation
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have added or updated documentation as needed

Additional context

[Copilot]

Pull Request Overview

This PR conditionally imports sample projects only when the current project is the root project, preventing unnecessary inclusion of samples when the SDK is used as a dependency in composite builds.

• Adds a conditional check to only include sample builds when gradle.parent == null
• Wraps the existing includeBuild statements for three sample projects in the conditional block

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[kpavlov]

That makes sense. Thank you for the PR, @jclyne