BE-1: Upgrade Stripe SDK to latest versions

[devin-ai-integration]

Summary

Upgrades both Stripe packages from legacy versions to latest stable releases:

• stripe: ^8.209.0 → ^22.0.1 (server-side SDK, 14 major versions)
• @stripe/stripe-js: ^1.25.0 → ^9.2.0 (client-side SDK, 8 major versions)

Server-side (pages/api/stripe.js):

• Added explicit apiVersion: '2026-03-25.dahlia' to the Stripe constructor (pins to the version bundled with SDK v22)
• Removed payment_method_types: ['card'] — Stripe now auto-determines payment methods from Dashboard config
• Removed shipping_options with hardcoded rate ID shr_1Kn3IaEnylLNWUqj5rqhg9oV (stale/environment-specific)

Client-side (components/Cart.jsx):

• Replaced stripe.redirectToCheckout({ sessionId }) with window.location.href = data.url — redirectToCheckout was removed in @stripe/stripe-js v9; the modern pattern uses the url returned by checkout.sessions.create
• Removed getStripe import and client-side Stripe.js instantiation (no longer needed for checkout redirect)

Review & Testing Checklist for Human

• Shipping options removed: The hardcoded shipping_rate: 'shr_1Kn3IaEnylLNWUqj5rqhg9oV' was removed entirely. If shipping is needed in checkout, a valid shipping rate must be re-added. Verify whether the store requires shipping configuration.
• Payment methods: Removing payment_method_types: ['card'] means Stripe will use whatever methods are enabled on the Stripe Dashboard. Confirm the account's Dashboard payment method settings are correct.
• Checkout redirect: The new flow relies on data.url from the session response. Test a full checkout flow (add to cart → pay → success page) against a Stripe test environment to confirm the redirect works.
• lib/getStripe.js is now dead code: The file still exists but is no longer imported. Consider removing it in a follow-up.

Recommended test plan: Run the app locally with valid Stripe test keys, add an item to cart, click "Pay with Stripe", and verify the Stripe Checkout page loads and the success/cancel redirects work.

Notes

• npm install required --legacy-peer-deps due to a pre-existing peer dependency conflict between @sanity/client@^3 and next-sanity-image (unrelated to this change).
• Build (next build) and lint (next lint) pass. All warnings are pre-existing.

Link to Devin session: https://app.devin.ai/sessions/2d16957bd0974e0887410360856a6c6f
Requested by: @Colhodm

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[devin-ai-integration]

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[devin-ai-integration]

✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no potential bugs to report.

View in Devin Review to see 3 additional findings.