Downgrade cart to guest cart on logout

[bookernath]

What/Why?

Opposite of #1765, downgrades customer cart to a guest cart whenever a shopper explicitly logs out.

Depends on new GQL capability that is not rolled out to 100% of stores yet, so do not merge label for now.

Testing

[changeset-bot]

🦋 Changeset detected

Latest commit: 7ac4f6f

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@bigcommerce/catalyst-core	Patch

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[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
catalyst-latest	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Dec 19, 2024 0:43am
catalyst-soul	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Dec 19, 2024 0:43am

3 Skipped Deployments

Name	Status	Preview	Comments	Updated (UTC)
catalyst	⬜️ Ignored (Inspect)			Dec 19, 2024 0:43am
catalyst-au	⬜️ Ignored (Inspect)			Dec 19, 2024 0:43am
catalyst-uk	⬜️ Ignored (Inspect)			Dec 19, 2024 0:43am

[github-actions]

⚡️🏠 Lighthouse report

Lighthouse ran against https://catalyst-latest-fh34uxv0q-bigcommerce-platform.vercel.app

🖥️ Desktop

We ran Lighthouse against the changes on a desktop and produced this report. Here's the summary:

Category	Score
🟠 Performance	82
🟢 Accessibility	96
🟢 Best practices	100
🟠 SEO	82

📱 Mobile

We ran Lighthouse against the changes on a mobile and produced this report. Here's the summary:

Category	Score
🟢 Performance	94
🟢 Accessibility	96
🟢 Best practices	100
🟠 SEO	85