[HACK] AI API keys: Hook keychain usage for AI feature

[iamgabrielma]

HACK week. Part of #15372

Description

Steps to reproduce

Testing information

Screenshots

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

[dangermattic]

	1 Message
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[wpmobilebot]

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

	App Name	WooCommerce iOS Prototype
	Build Number	pr16150-9111c1d
	Version	23.2
	Bundle ID	com.automattic.alpha.woocommerce
	Commit	9111c1d
	Installation URL	7muajh44pfqbo

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[iamgabrielma]

Closing: pdfdoF-85K#comment-9421-p2