fix(core): revert Next 15 upgrade

[deini]

What/Why?

Revert Next 15 upgrade. All static pages are returning 404 on dev mode starting on 15.0.1.

Downgrading to 14 while we investigate.

[changeset-bot[bot]]

⚠️ No Changeset found

Latest commit: b90d85214ee8d09edf90bc99eb1aee723d77848f

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[vercel[bot]]

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Name	Status	Preview	Comments	Updated (UTC)
catalyst-latest	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Oct 30, 2024 4:32pm

6 Skipped Deployments

| Name | Status | Preview | Comments | Updated (UTC) | | :--- | :----- | :------ | :------- | :------ | | **catalyst** | ⬜️ Ignored ([Inspect](https://vercel.com/bigcommerce-platform/catalyst/9L21pjP5KQgD4sbaA42bjqz264mR)) | | | Oct 30, 2024 4:32pm | | **catalyst-1millionproducts-store** | ⬜️ Ignored ([Inspect](https://vercel.com/bigcommerce-platform/catalyst-1millionproducts-store/34zWPnaPScBDFWXMSmmPAqryWok8)) | [Visit Preview](https://catalyst-1millionproducts-store-git-d78bcb-bigcommerce-platform.vercel.app) | | Oct 30, 2024 4:32pm | | **catalyst-au** | ⬜️ Ignored ([Inspect](https://vercel.com/bigcommerce-platform/catalyst-au/AmmTx7FHM6rvs5R2iccQQpUY9VmH)) | [Visit Preview](https://catalyst-au-git-revert-next-15-bigcommerce-platform.vercel.app) | | Oct 30, 2024 4:32pm | | **catalyst-test-store** | ⬜️ Ignored ([Inspect](https://vercel.com/bigcommerce-platform/catalyst-test-store/7ZQJBy3qk1TRBZhGzWaChrkNLsmW)) | [Visit Preview](https://catalyst-test-store-git-revert-next-15-bigcommerce-platform.vercel.app) | | Oct 30, 2024 4:32pm | | **catalyst-uk** | ⬜️ Ignored ([Inspect](https://vercel.com/bigcommerce-platform/catalyst-uk/3Yv2TzjjtRvsDm6FGxqu359zCiuE)) | [Visit Preview](https://catalyst-uk-git-revert-next-15-bigcommerce-platform.vercel.app) | | Oct 30, 2024 4:32pm | | **catalyst-unstable** | ⬜️ Ignored ([Inspect](https://vercel.com/bigcommerce-platform/catalyst-unstable/39Tj9yJ4pmrAj1UP74F7tzgxDV2J)) | [Visit Preview](https://catalyst-unstable-git-revert-next-15-bigcommerce-platform.vercel.app) | | Oct 30, 2024 4:32pm |

[github-actions[bot]]

⚡️🏠 Lighthouse report

Lighthouse ran against https://catalyst-latest-odm0cyvr1-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	78
🟢 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	95
🟢 Accessibility	96
🟢 Best practices	100
🟠 SEO	85