feat: implémenter processBatch et downloadAllAsZip

js/imageProcessor.js

@@ -1,3 +1,17 @@
+/**
+ * Traite un tableau d'items avec au plus `concurrency` appels simultanés.
+ * @param {any[]} items
+ * @param {(item: any) => Promise<void>} processFn
+ * @param {number} concurrency
+ * @returns {Promise<void>}
+ */
 export async function processBatch(items, processFn, concurrency = 3) {
-  throw new Error('Not implemented');
+  const queue = [...items];
+  const workers = Array.from({ length: concurrency }, async () => {
+    while (queue.length > 0) {
+      const item = queue.shift();
+      if (item !== undefined) await processFn(item);
+    }
+  });
+  await Promise.all(workers);
 }