feat: add reusable commerce storefront package

[sbolinger-godaddy]

What changed

• Added reusable Commerce storefront components for product browsing, product details, carts, and checkout.
• Added a Commerce server package containing the matching catalog, cart, checkout, and order-status APIs.
• Included built-in styling, documentation, tests, and a standalone example.
• Kept application-owned concerns—routing, merchant setup, runtime configuration, and framework providers—outside the packages.

Why

This moves shared Commerce implementation out of generated customer applications. App Builder can now install a small, consistent integration instead of generating and maintaining many frontend and server files for every app.

The result is less duplicated code, simpler agent instructions, and centralized fixes while preserving existing customized applications.

Testing

I ran about 20 manual comparison builds, what we have on main vs this PR, here's the results:

50% faster (5 mins vs 10+ mins)
34% fewer execution steps (133 vs 205)
41% cheaper ($3.63 vs $6.34)

[changeset-bot]

🦋 Changeset detected

Latest commit: 5314b51

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

This PR includes changesets to release 2 packages

Name	Type
@godaddy/commerce-server	Minor
@godaddy/commerce-storefront	Minor

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