Non-Blocking Async Socket Handler - Quant Developer Interview Question

Problem Description

Non-blocking network I/O is critical in low-latency trading systems to maintain continuous execution without stalling on socket operations. This requires robust application-level buffering and message framing to handle stream fragmentation and bandwidth constraints. The task involves simulating an asynchronous socket handler that manages output queuing and parses length-prefixed incoming messages. Task Implement a class AsyncHandler and a driver function solution to simulate a non-blocking sock