Replace QuickESPNow with local library (#5624)

* initial version, fully reviewed but untested
* add support for missing RSSI in IDF V4
* optimize: make sending more robust
* add namespace, move to lib\
* volatile -> atomic plus some comment cleanup
* fix & simplify sending function, fix for ESP8266
* remove stray DCO again, enable espnow on C6 (tested working) and C5 (assumed working)

* fix signature of espnowSentCB for IDF V5.5, comments, P4 compile fix

* fix esp8266_2m_min env