Add barcode scanner integration, identifier lookup, and enhanced field mapping for label creation

src/api/stock.js

@@ -68,6 +68,18 @@ function normalizeUpsertResponse(payload) {
   };
 }
 
+function normalizeIdentifierLookupResponse(payload) {
+  return {
+    status: payload?.status || null,
+    source: payload?.source || null,
+    cacheHit: Boolean(payload?.cache_hit),
+    identifierCode: payload?.identifier_code || null,
+    identifierType: payload?.identifier_type || null,
+    item: payload?.item || null,
+    payloadFetchedAt: payload?.payload_fetched_at || null,
+  };
+}
+
 export async function previewItemUpsert(store, body) {
   const payload = await apiRequest(store, `${getPath('items')}/upsert`, {
     method: 'POST',
@@ -88,6 +100,17 @@ export async function applyItemUpsert(store, body) {
   return normalizeUpsertResponse(payload);
 }
 
+export async function lookupItemByIdentifier(store, identifierCode) {
+  const payload = await apiRequest(store, `${getPath('items')}/lookup`, {
+    method: 'POST',
+    body: {
+      identifier_code: String(identifierCode || '').trim(),
+    },
+  });
+
+  return normalizeIdentifierLookupResponse(payload);
+}
+
 export async function updateStockItem(store, uuidB64, body) {
   const payload = await apiRequest(store, `${getPath('items')}/${uuidB64}/stock`, {
     method: 'POST',