Add support for Qingping CGG3 (Temp RH M, product ID 0x4F) #721

Hello,

The Qingping CGG3 (Temp RH M) is currently not decoded by Theengs Decoder. Theengs Gateway only publishes the raw advertisement:

{"name": "Qingping Temp RH", "id": "58:2D:34:87:08:30", "rssi": -82, "servicedatauuid": "fdcd", "servicedata": "884f300887342d580104d100f201020164"}

The frame has exactly the same layout as the CGG1 stock firmware (product ID 07 / 16); only the product ID differs (0x4F):

88 | 4F | 300887342D58 (reversed MAC) | 01 04 D100 F201 (temp 20.9 °C, hum 49.8 %) | 02 01 64 (battery 100 %)

Product ID 0x4F = CGG3 is also used by bluetooth-devices/qingping-ble (Home Assistant).

Attached is a patch that:

• adds src/devices/CGG3_json.h (based on the CGG1 stock decoder, condition on product ID 4f)
• registers it in decoder.h and devices.h
• adds a unit test with a real CGG3 frame

All tests pass, and I tested it on my Theengs Gateway (Jeedom): the CGG3 is now decoded with tempc, hum, batt and mac.

Thanks!

theengs-decoder-cgg3.txt