fixes the airlock power buttons for silicons (#76574)

## About The Pull Request

both values tend to be null or 0

## Why It's Good For The Game

fixes #76571

## Changelog
🆑
fix: silicons can depower airlocks via their UI again
/🆑

code/game/machinery/doors/airlock.dm

@@ -1569,9 +1569,9 @@
 
 	var/list/power = list()
 	power["main"] = remaining_main_outage() ? 0 : 2 // boolean
-	power["main_timeleft"] = remaining_main_outage()
+	power["main_timeleft"] = round(remaining_main_outage() / 10)
 	power["backup"] = remaining_backup_outage() ? 0 : 2 // boolean
-	power["backup_timeleft"] = remaining_backup_outage()
+	power["backup_timeleft"] = round(remaining_backup_outage() / 10)
 	data["power"] = power
 
 	data["shock"] = secondsElectrified == MACHINE_NOT_ELECTRIFIED ? 2 : 0
@@ -1609,14 +1609,14 @@
 		return
 	switch(action)
 		if("disrupt-main")
-			if(remaining_main_outage())
+			if(!main_power_timer)
 				loseMainPower()
 				update_appearance()
 			else
 				to_chat(usr, span_warning("Main power is already offline."))
 			. = TRUE
 		if("disrupt-backup")
-			if(remaining_backup_outage())
+			if(!backup_power_timer)
 				loseBackupPower()
 				update_appearance()
 			else