Refactor: eliminate code duplication and extract shared utilities (#13)

* Extract extractBasePath and getPathWithoutPrefix to shared utility

Consolidate 10 duplicate copies of extractBasePath and 2 copies of
getPathWithoutPrefix into a single shared module at src/lib/utils/path.ts.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Extract actionResult and withFallback helpers for server actions

Replace 16 identical try/catch blocks across 7 data files with two
shared helpers: actionResult (for mutation results) and withFallback
(for fetch-or-default queries).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Extract product listing logic into shared hook, layout, and utility

- buildProductQueryParams: shared filter-to-query-params conversion
- useProductListing: shared state, pagination, infinite scroll, filter fetching
- ProductListingLayout: shared filter sidebar, skeleton, empty state, load-more UI

ProductsContent shrinks from 410 to 62 lines, CategoryProductsContent
from 373 to 39 lines.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Remove dead internal fetch and useEffect anti-pattern from ProductFilters

- Remove unused internal filter fetching state/effect (~30 lines dead code)
- Remove useStore and getProductFilters imports (no longer needed)
- Make filtersData and loading required props
- Replace useEffect-based onFilterChange with direct calls via updateFilters helper
- Eliminates an unnecessary render cycle on every filter change

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Extract mutateCart helper in CartContext

Replace 3 structurally identical cart mutation callbacks (addItem,
updateItem, removeItem) with a shared mutateCart helper that handles
the setUpdating/result.success/router.refresh pattern.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Extract toUser mapper in AuthContext

Replace 3 identical user-object constructions in refreshUser, login,
and register with a shared toUser helper function.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Centralize cookie helpers and break up StoreContext useEffect

- Extract setStoreCookies helper to src/lib/utils/cookies.ts,
  replacing duplicated document.cookie calls with magic numbers
- Extract resolveCountryAndCurrency as a pure function from the
  68-line useEffect in StoreContext, improving readability
- Add explicit eslint-disable comment for intentionally excluded
  pathname dependency

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Standardize context conventions and minor cleanups

- Standardize CheckoutContext to use undefined (matching Cart, Auth,
  Store contexts) instead of null
- Remove unnecessary fragment wrapper in CountrySwitcher
- Remove unused currentCountry variable in CountrySwitcher
- Merge two redundant guard blocks in account layout into one

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Extract shared address types and utilities to eliminate duplication

Consolidate AddressFormData, emptyAddress, addressToFormData, formDataToAddress,
and addressesMatch from 4 files into src/lib/utils/address.ts, removing ~250
lines of duplicated code.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Extract AddressFormFields and AddressEditModal shared components

Replace 4 copies of address form fields (AddressStep, AddressSelector,
PaymentStep BillingAddressForm, account AddressModal) with a single shared
AddressFormFields component. Extract AddressEditModal to replace duplicated
modal+form+state logic in AddressStep and account addresses page.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Fix pre-existing TypeScript errors in orders.ts and checkout page

- Add missing `meta` field to orders fallback to match PaginatedResponse type
- Fix type narrowing for updateAddress result by checking `!result.success` first

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Address CodeRabbit review feedback

- Add catch block to mutateCart for unhandled network errors
- Return spread copy from addressToFormData to prevent shared state mutation
- Simplify toUser parameter to use User type directly
- Move billing address reset from useEffect to onChange handler
- Add accessibility attrs to AddressEditModal (role, aria-modal, escape key)
- Fix side effect in ProductFilters state updater

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Address PR #13 review feedback

- Fix race condition in useProductListing with loadIdRef guard for
  both loadProducts and loadMore to prevent stale results
- Add .catch handlers to fetchStates in AddressEditModal and
  PaymentStep to prevent unhandled promise rejections
- Simplify handleUpdateSavedAddress with early-return guard clauses
- Throw instead of silently returning in handleSaveEditedAddress
- Fix PriceFilter inputs not resetting on clearFilters via key prop
- Add error logging to withFallback for production observability
- Use neutral fallback message in applyCouponCode
- Encode cookie values in setStoreCookies
- Spread emptyAddress to avoid shared mutable reference

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* ADD throw error when no variant selected

* FIX: Checkout steps

* ADD Password preview

* FIX aria and cosmetics changes

* REFACTOR method of implementation svg

* FIX lint

* FIX lint single-line error

* FIX tests for svgr

* FIX coderabbits comments

* FIX older coderabbits comments

* FIX lint

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: Filip Cichorek <cichorek.filip@gmail.com>

Author: 3 people

next.config.ts

@@ -2,6 +2,21 @@ import type { NextConfig } from "next";
 
 const nextConfig: NextConfig = {
   transpilePackages: ["@spree/next", "@spree/sdk"],
+  turbopack: {
+    rules: {
+      "*.svg": {
+        loaders: ["@svgr/webpack"],
+        as: "*.js",
+      },
+    },
+  },
+  webpack(config) {
+    config.module.rules.push({
+      test: /\.svg$/,
+      use: ["@svgr/webpack"],
+    });
+    return config;
+  },
   images: {
     qualities: [25, 50, 75, 100],
     dangerouslyAllowLocalIP: true, // Allow localhost images in development