A robust, thread-safe ping implementation for ESP32, designed for multitasking environments.

• Thread‑safe
  Works reliably inside multiple FreeRTOS tasks without packet collisions.

• Intermediate result reporting
  Override onReceive() and onWait() to display progress in real time.

• Non‑blocking operation
  Uses raw sockets in non-blocking mode for precise timeout handling.

• Accurate timing
  Round-trip time measured using micros() with microsecond precision.

• Incremental statistics
  Mean, variance, min/max latency computed without storing all samples.

• Compatible with Arduino IDE

Existing ESP32 ping libraries are excellent foundations, but they lack:

• thread-safety

• non-blocking operation

• intermediate result callbacks