rx duty cycle rework

zephcore/src/main_repeater.cpp

@@ -474,11 +474,9 @@ int main(void)
 		}
 	}
 
-	/* Apply RX boost from prefs.  Duty cycle is disabled — CAD-based
-	 * duty cycling misses weak packets that continuous RX would catch.
-	 * Arduino reference uses continuous RX for all boards. */
+	/* Apply RX boost and duty cycle from prefs */
 	lora_radio.setRxBoost(prefs->rx_boost != 0);
-	lora_radio.enableRxDutyCycle(false);
+	lora_radio.enableRxDutyCycle(prefs->rx_duty_cycle != 0);
 
 	/* Feed initial UI state from loaded prefs */
 	ui_set_node_name(prefs->node_name);