feat(iot): Add alerts for shelly devices

This patch introduces some useful alerts regarding humidity and
room temprature in order to keep all rooms managed. This will be
especially handy while being outside, or on holiday. It's reusing
the regular notification infrastructure that exists for the
cluster anyway.

The alerts for humidity trigger a warning after 6 hours if the
humidity is above 65% and 30 minutes as critical when the
humidity is above 80%.

It also triggers a warning when tempratures climb above 25°C
for 6 hours or a critical alert when tempratures exceed 28°C
for more than 30 minutes.

Finally when tempratures drop too low, increasing the risk of
mold, a warning is triggered at tempratures below 20°C after 6
hours and a critical alert is triggered when the temprature
falls below 18°C for more than 30 minutes.

References:
https://www.restorationservicesil.com/what-best-temperature-prevent-mold/