fix(ac): allow half-degree integer temperatures

[folfy]

This is deduplicating the temperature functions, and then finally dropping the int(...) cast on the "integer" temperature value. This is used on e.g. the Midea PortaSplit, which reports half-degree values via this field (decimal value = 0).

I'd think if a device reports a decimal value as int + decimal, then it won't report half-degree steps for the integer, and the casting of the integer would be redundant. To be on the safe side though, and avoid potential regressions, I've implemented it to only return the integer as float, if the decimal really is 0. So even if the integer is reported with half-degree steps and a seperate decimal simultaneously, it'd be fine, since in that case the integer should be a whole number anyway.

PS: Let me know if and what you'd want as "proof", e.g. HA or Midea-App screenshots, debug logs (before or after fix), etc., and I'll provide it (just don't want to waste time on unnecessary stuff)

[folfy]

Fixed ruff and mypy issues (https://github.com/midea-lan/midea-local/actions/runs/19017035037/job/54319895649?pr=412)

Changes (merged commit via force-push): b07cdbe

[wuwentao]

thank you very much for your PR.
merged!