Fix and improve code samples

[alexandersandberg]

Description of what this PR is changing or adding, and why:

• Fixed "Styling buttons" SwiftUI code sample
• Fixed inconsistent indentation in code samples

Issues fixed by this PR (if any):

PRs or commits this PR depends on (if any):

Presubmit checklist

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[gemini-code-assist]

Code Review

This pull request standardizes the indentation of SwiftUI code snippets in the documentation to a 2-space format and corrects a syntax error in a button example. A review comment suggests adding a .padding() modifier to the button styling example to ensure parity with the corresponding Flutter example and recommends indenting view modifiers for consistency with other sections.

[sfshaza2]

/gcbrun

[flutter-website-bot]

Visit the preview URL for this PR (updated for commit beb2cb2):

https://flutter-docs-prod--pr13312-patch-1-h1lm5hoo.web.app

[redbrogdon]

LGTM. Thanks for tidying it up.

The bit about padding is weird. I'd argue that rather than adding it to the Swift code we should remove it from the Flutter example, since AFAICT it's not part of the point they're making about colors.

Either way, it's nothing this PR needs to address.