ESP32 ULP Coprocessor

**Describe the problem you have/What new integration you would like**

Possibility to set the counter of impulses on the coprocessor. And the main core of ESP32 is sleeping.

**Please describe your use case for this integration and alternatives you've tried:**

Pulse counter for metering water consumption. Less battery consumption!

**Additional context**

https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-guides/ulp.html
https://github.com/tanakamasayuki/UlpDebug
Real Project Water Counter:
https://github.com/OloloevReal/Waterius32/tree/master/src

Start with the linked ESP-IDF ULP documentation and the UlpDebug repository, then inspect the Waterius32 `src` directory for its water-counter approach. Determine how an ESP32 ULP pulse counter could integrate while the main core sleeps; done should include reliable metering with lower battery consumption.

Written by the indexing model from the issue text.