Harden bulk retries, parallelize guest uploads, and move guest map below gallery

apps/web/src/lib/upload-queue.ts

@@ -0,0 +1,23 @@
+// Keep a few transfers in flight without flooding mobile connections or allocating
+// a promise/network request for every selected file at once.
+export const UPLOAD_CONCURRENCY = 3;
+
+export async function runUploadQueue<T>(
+  items: readonly T[],
+  upload: (item: T, index: number) => Promise<void>,
+) {
+  let next = 0;
+  const errors: unknown[] = [];
+  await Promise.all(Array.from({ length: Math.min(UPLOAD_CONCURRENCY, items.length) }, async () => {
+    while (next < items.length) {
+      const index = next++;
+      try {
+        await upload(items[index]!, index);
+      } catch (error) {
+        errors.push(error);
+      }
+    }
+  }));
+  // Never release the batch's busy guard while other transfers are still running.
+  if (errors.length) throw new AggregateError(errors, "Some uploads failed");
+}