docs: add catalyst-client documentation

[bc-andreadao]

What/Why?

Document how to use the client for fetching data from BigCommerce Storefront API

Methods have their parameters, return values, etc. documented (e.g. how to use client.fetch(), etc)

Testing

N / A

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Latest commit: 1d42ad11b0088b40b4ce8090672944d3ac66168a

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Name	Status	Preview	Comments	Updated (UTC)
catalyst-latest	✅ Ready (Inspect)	Visit Preview		Sep 13, 2024 3:36am

5 Skipped Deployments

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[github-actions[bot]]

⚡️🏠 Lighthouse report

Lighthouse ran against https://catalyst-latest-7pmfs9c4z-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	100
🟢 Accessibility	100
🟢 Best practices	96
🟠 SEO	82

📱 Mobile

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

Category	Score
🟢 Performance	97
🟢 Accessibility	100
🟢 Best practices	96
🟠 SEO	85