[WIP] Add changeset file for GitHub Copilot integration

[Copilot]

Thanks for assigning this issue to me. I'm starting to work on it and will keep this PR's description up to date as I form a plan and make progress.

Original prompt

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This section details on the original issue you should resolve

<issue_title>## Pull Request Overview</issue_title>
<issue_description>## Pull Request Overview

This PR adds a changeset file to document setup steps for GitHub Copilot integration. The changeset indicates patch-level updates across multiple packages in the Reown AppKit ecosystem to support Copilot functionality.

• Introduces a changeset file documenting Copilot setup steps
• Applies patch updates to UI, controllers, scaffold UI components and gallery app

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_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}

Originally posted by @copilot-pull-request-reviewer in reown-com/appkit#5084 (review)</issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes #255

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💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[joe10832]

@copilot