-disable GPS cycle until reboot if no GNSS messages present
-make our sx driver more aligned with radiolib's logics (BUSY-line timeout protection, Wake-from-sleep robustness)
-runtime guard agc reset if rx duty cycle is enabled
-tune delay knobs (move closer to vanilla values)
-refactor repeater prefs changes (fix prefs not stored / overwritten on a second "set" command AND don't apply new radio prefs before reboot)
-micro-tweak: skip APC math when APC is off
-port vanilla duty cycling logic and replace our coarse method
-fix RX duty cycling logic (it was 9symbol rx / 6symbol sleep instead of 10/6)