Method push

packages/runtime/src/internal/AsyncQueue.ts:44–56

* Push an item to the queue * * If there's a waiting consumer, deliver directly (no buffering). * Otherwise, buffer the item for later consumption.

(item: T)

   * Otherwise, buffer the item for later consumption.
   */
  push(item: T): void {
    if (this.closed) return;

    // Key: Check if there's a waiting consumer FIRST
    if (this.waiting.length > 0) {
      // Deliver directly to waiting consumer (no race condition)
      const resolve = this.waiting.shift()!;
      resolve({ done: false, value: item });
    } else {
      // No waiting consumer, buffer the item
      this.buffer.push(item);
    }
  }

  /**
   * Close the queue