add gr.Success and update windows contributing

[not-lain]

Description

in this pr we add gr.Success && we updated CONTRIBUTING.md to support windows

Closes: #7489

[gradio-pr-bot]

🪼 branch checks and previews

•	Name	Status	URL
	Spaces	ready!	Spaces preview
	Website	ready!	Website preview
	Storybook	ready!	Storybook preview
🦄	Changes	detected!	Details

---

Install Gradio from this PR

pip install https://gradio-pypi-previews.s3.amazonaws.com/87490e853399cd6106c32e8466d7a07a38c39469/gradio-5.9.1-py3-none-any.whl

Install Gradio Python Client from this PR

pip install "gradio-client @ git+https://github.com/gradio-app/gradio@87490e853399cd6106c32e8466d7a07a38c39469#subdirectory=client/python"

Install Gradio JS Client from this PR

npm install https://gradio-npm-previews.s3.amazonaws.com/87490e853399cd6106c32e8466d7a07a38c39469/gradio-client-1.8.0.tgz

Use Lite from this PR

<script type="module" src="https://gradio-lite-previews.s3.amazonaws.com/87490e853399cd6106c32e8466d7a07a38c39469/dist/lite.js""></script>

[gradio-pr-bot]

🦄 change detected

This Pull Request includes changes to the following packages.

Package	Version
@gradio/client	minor
@gradio/icons	minor
@gradio/statustracker	minor
gradio	minor

• Maintainers can select this checkbox to manually select packages to update.

With the following changelog entry.

add gr.Success and update windows contributing

Maintainers or the PR author can modify the PR title to modify this entry.

Something isn't right?

• Maintainers can change the version label to modify the version bump.
• If the bot has failed to detect any changes, or if this pull request needs to update multiple packages to different versions or requires a more comprehensive changelog entry, maintainers can update the changelog file directly.

[abidlabs]

Very cool @not-lain, will take a look!

[abidlabs]

lgtm @not-lain great PR!