Add fan/ventilation speed support for Bosch compress 3800i/IVT Vent 402

[proddy]

Discussed in #1690

^{Originally posted by mattfro April 10, 2024}
Add fan control support. On this device I think you cannot turn off the fan and the min value is 20% and max 100%
I was trying to understand ems messages so(but I have no idea), if I guess correct, 40% should be 28 and 41% should be 29?
If that is the case, I think I fetched when I was changing the value in the pump between 40 and 41.
[K000+00:45:56.777 T 9959: [emsesp] controller(0x09) -W-> boiler(0x08), ?(0x04A5), data: 29 (offset 9)
[K000+00:46:01.127 T 9997: [emsesp] controller(0x09) -W-> boiler(0x08), ?(0x04A5), data: 28 (offset 9)
[K000+00:46:06.064 T 10064: [emsesp] controller(0x09) -W-> boiler(0x08), ?(0x04A5), data: 29 (offset 9)
[K000+00:46:08.889 T 10103: [emsesp] controller(0x09) -W-> boiler(0x08), ?(0x04A5), data: 28 (offset 9)
[K000+00:46:11.627 T 10146: [emsesp] controller(0x09) -W-> boiler(0x08), ?(0x04A5), data: 29 (offset 9)
[K000+00:46:15.552 T 10191: [emsesp] controller(0x09) -W-> boiler(0x08), ?(0x04A5), data: 28 (offset 9)
Last value I left it on was 40%

[MichaelDvP]

It's already in the dev.

EMS-ESP32/src/devices/boiler.cpp

Line 805 in 13e7a53

register_device_value(DeviceValueTAG::TAG_DEVICE_DATA, &fan_, DeviceValueType::UINT8, FL_(hpFan), DeviceValueUOM::PERCENT, MAKE_CF_CB(set_fan), 20, 100);