fix: now "Suggested by AI" label is visible in dark mode in Blaze Edit

[pmusolino]

Closes: #14138

Description

This pull request addresses a visibility issue with the "Suggested by AI" label in dark mode.

Testing information

1. Log into a Blaze-eligible site.
2. Trigger the Blaze campaign creation flow.
3. Switch to dark mode.
4. Observe the "Suggested by AI" label and verify its visibility.

Screenshots

Light mode	Dark mode

---

• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

Reviewer (or Author, in the case of optional code reviews):

Please make sure these conditions are met before approving the PR, or request changes if the PR needs improvement:

• The PR is small and has a clear, single focus, or a valid explanation is provided in the description. If needed, please request to split it into smaller PRs.
• Ensure Adequate Unit Test Coverage: The changes are reasonably covered by unit tests or an explanation is provided in the PR description.
• Manual Testing: The author listed all the tests they ran, including smoke tests when needed (e.g., for refactorings). The reviewer confirmed that the PR works as expected on all devices (phone/tablet) and no regressions are added.

[wpmobilebot]

📲 You can test the changes from this Pull Request in WooCommerce iOS by scanning the QR code below to install the corresponding build.

	App Name	WooCommerce iOS
	Build Number	pr15088-0267b58
	Version	21.7
	Bundle ID	com.automattic.alpha.woocommerce
	Commit	0267b58
	App Center Build	WooCommerce - Prototype Builds #12884

Automatticians: You can use our internal self-serve MC tool to give yourself access to App Center if needed.

[itsmeichigo]

I was wondering why the label colors were not re-rendered when switching between light & dark mode.

I checked the code and found that we were applying .environment(\.colorScheme, .light) to the whole adPreview view, while in fact we should apply it to the VStack containing the preview only.

That way, both the "Suggested by AI" label and "Edit Ad" button would be in the correct colors without having to apply different colors using colorScheme like your fix.

WDYT?

[pmusolino]

@itsmeichigo yes I think it makes sense, I updated it here 76a310d

[wpmobilebot]

Version 21.7 has now entered code-freeze, so the milestone of this PR has been updated to 21.8.

[itsmeichigo]

This should be moved to 21.8