Fix cart items not visible on return visit until new item added

[Niki-Tester]

• Add useEffect to load cart from localStorage on component mount
• When cardId exists in storage but Redux state is empty/different, trigger getCartDetails to restore persisted cart items
• Fixes [bug]: Cart items not visible on return visit until a new item is added #4585

Description

Added a useEffect hook to the CartContextProvider component that automatically loads the cart from localStorage when the component mounts. This ensures that when users return to the application after closing the tab or reloading the page, their previously added cart items are restored.

The effect checks if a cartId exists in localStorage, and if the Redux cartState is either empty or has a different cartId, it triggers asyncActions.getCartDetails() to fetch and restore the persisted cart data.

Related Issue

Closes #4585

Acceptance

Verification Stakeholders

Specification

Verification Steps

1. Start with an empty cart
2. Add one or more items to the cart (verify item is added and cartId is stored in localStorage)
3. Reload the page
4. Verify cart items are still visible and restored (no need to add another item to see them)
5. Close the browser tab completely and reopen the application
6. Verify cart items are still visible and restored

Test scenario(s) for direct fix/feature

Test scenario(s) for any existing impacted features/areas

Test scenario(s) for any Magento Backend Supported Configurations

Is Browser/Device testing needed?

Any ad-hoc/edge case scenarios that need to be considered?

Screenshots / Screen Captures (if appropriate)

Breaking Changes (if any)

Checklist

• I have added tests to cover my changes, if necessary.
• I have added translations for new strings, if necessary.
• I have updated the documentation accordingly, if necessary.

[pwa-studio-bot]

	Fails
🚫	node failed.
🚫	Cypress tests in the following files did not pass 😔. All tests must pass before this PR can be merged displays assigned products: AssertionError: Timed out retrying after 30000ms: Expected to find element: `[data-cy="CategoryContent-root"] [data-cy="GalleryItem-name"], [data-cy="SearchPage-root"] [data-cy="GalleryItem-name"]`, but never found it. ,shows products specific to the categories in the different store: AssertionError: Timed out retrying after 30000ms: Expected to find element: `[data-cy="CategoryContent-root"] [data-cy="GalleryItem-name"], [data-cy="SearchPage-root"] [data-cy="GalleryItem-name"]`, but never found it. ,lets users add products to cart regardless of store view: AssertionError: Timed out retrying after 30000ms: Expected to find element: `[data-cy="CategoryContent-root"] [data-cy="GalleryItem-root"]`, but never found it.

Log

ERROR ON TASK: cypressTests

Error:  Danger had errors running. See message(s) above for more details.
danger-results://tmp/danger-results.json

Generated by 🚫 dangerJS against 1f6546c

[pwa-studio-bot]

	Fails
🚫	node failed.

Log

ERROR ON TASK: cypressTests

Error:  Danger had errors running. See message(s) above for more details.
danger-results://tmp/danger-results.json

Generated by 🚫 dangerJS against 1f6546c

[pwa-studio-bot]

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Generated by 🚫 dangerJS against 1f6546c

[pwa-studio-bot]

	Fails
🚫	Lighthouse assertions failed 😔. All assertions must pass before this PR can be merged https://pr-4586.pwa-venia.com/ First Contentful Paint (maxNumericValue) Expected: 2900 Actual: 2908.897 Result: Failed Docs link: https://developer.chrome.com/docs/lighthouse/performance/first-contentful-paint/ https://pr-4586.pwa-venia.com/valeria-two-layer-tank.html First Contentful Paint (maxNumericValue) Expected: 3200 Actual: 3201.343 Result: Failed Docs link: https://developer.chrome.com/docs/lighthouse/performance/first-contentful-paint/ Total Blocking Time (minScore) Expected: 0.2 Actual: 0.17 Result: Failed Docs link: https://developer.chrome.com/docs/lighthouse/performance/lighthouse-total-blocking-time/
🚫	node failed.

Log

Details

ERROR ON TASK: lighthouseTests

Error:  Danger had errors running. See message(s) above for more details.
danger-results://tmp/danger-results-6c02d85a.json

Generated by 🚫 dangerJS against 1f6546c