Make some @objc methods public so WordPressData can access them

[mokagio]

I never looked into it, but apparently the public access level for @objc is required in a framework setup for those methods to be accessible through the <framework name>-Swift.h generated header.

We run into the same issue in Keystone, see #24383

Part of #24165

[dangermattic]

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⚠️	This PR is assigned to the milestone 25.9. The due date for this milestone has already passed. Please assign it to a milestone with a later deadline or check whether the release for this milestone has already been finished.

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[wpmobilebot]

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

	App Name	WordPress
	Configuration	Release-Alpha
	Build Number	27010
	Version	PR #24386
	Bundle ID	org.wordpress.alpha
	Commit	932f1dd
	Installation URL	515bhgjct8tgo

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[wpmobilebot]

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

	App Name	Jetpack
	Configuration	Release-Alpha
	Build Number	27010
	Version	PR #24386
	Bundle ID	com.jetpack.alpha
	Commit	932f1dd
	Installation URL	0n64q0l2olmqg

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