fix: vérifier l'existence Shopify avant création pour éviter les doublons

- Chargement du catalogue Shopify au début de l'exécution (fetchAllShopifyProducts)
- Vérification par SKU (ref) : si déjà présent dans Shopify → skipped, pas de création
- Nouveau type d'événement 'skipped' dans CreationStreamEvent
- CreationProgress affiche les produits ignorés en amber avec le SKU concerné
- Résumé final inclut le compte de produits ignorés

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

src/app/api/creation/execute/route.ts

@@ -5,7 +5,7 @@ import { fetchPendingProducts } from '@/lib/creationSheets'
 import { generateDescriptions } from '@/lib/openaiClient'
 import { ensureMetafieldDefinition, setProductMetafield } from '@/lib/shopifyMetafields'
 import { addProductToCollection } from '@/lib/shopifyCollections'
-import { createShopifyProduct } from '@/lib/shopifySync'
+import { createShopifyProduct, fetchAllShopifyProducts } from '@/lib/shopifySync'
 import { prisma } from '@/lib/prisma'
 import type { MetafieldResolution, CreationStreamEvent } from '@/types/creation'
 
@@ -28,13 +28,17 @@ export async function POST(req: NextRequest) {
     async start(controller) {
       const send = (event: CreationStreamEvent) => controller.enqueue(encode(event))
       try {
-        const existing = await prisma.productCreation.findMany({ select: { sheetTab: true, sheetRow: true } })
-        const alreadyCreated = new Set(existing.map(e => `${e.sheetTab}:${e.sheetRow}`))
+        const [existingRows, shopifyProducts] = await Promise.all([
+          prisma.productCreation.findMany({ select: { sheetTab: true, sheetRow: true } }),
+          fetchAllShopifyProducts(),
+        ])
+        const alreadyCreated = new Set(existingRows.map(e => `${e.sheetTab}:${e.sheetRow}`))
+        const shopifyRefs = new Set(shopifyProducts.map(p => p.ref.trim().toLowerCase()))
         const pending = await fetchPendingProducts(alreadyCreated)
         const total = pending.length
 
         if (total === 0) {
-          send({ type: 'done', summary: { created: 0, errors: 0, status: 'success' } })
+          send({ type: 'done', summary: { created: 0, skipped: 0, errors: 0, status: 'success' } })
           controller.close()
           return
         }
@@ -45,10 +49,19 @@ export async function POST(req: NextRequest) {
         }
 
         let created = 0
+        let skipped = 0
         let errors = 0
 
         for (let i = 0; i < pending.length; i++) {
           const product = pending[i]
+
+          // Vérifier si le produit existe déjà dans Shopify par SKU
+          if (shopifyRefs.has(product.sku.trim().toLowerCase())) {
+            send({ type: 'skipped', title: product.title, sku: product.sku })
+            skipped++
+            continue
+          }
+
           send({ type: 'progress', current: i + 1, total, tab: product.tab, title: product.title, step: 'Génération descriptions…' })
           try {
             const { longDesc } = await generateDescriptions({
@@ -90,10 +103,10 @@ export async function POST(req: NextRequest) {
           }
         }
         const status = errors === 0 ? 'success' : created === 0 ? 'error' : 'partial'
-        send({ type: 'done', summary: { created, errors, status } })
+        send({ type: 'done', summary: { created, skipped, errors, status } })
       } catch (err) {
         const message = err instanceof Error ? err.message : 'Erreur inconnue'
-        send({ type: 'done', summary: { created: 0, errors: 1, status: 'error' } })
+        send({ type: 'done', summary: { created: 0, skipped: 0, errors: 1, status: 'error' } })
         console.error('[creation/execute]', message)
       } finally {
         controller.close()