Wires Panel and Signaler Expansion (#22846)

Fleshes out wire panel skill behavior and signaler management.

Electrical Engineering 4 was very OP for revealing all wire labels of
all machines, and it was super fun while it lasted.

Wire panels now have associated skills with their use, and increased
skill ranks will increase the proportion of wires (chosen at random)
that are easily recognizable on sight for certain types of wiring
panels.
**Professional:** 75% revealed
**Trained:** 50% revealed
**Familiar:** 30% revealed
_(note: having both Electrical and Mechanical engineering at least
Trained gives you that baseline 30%, reflecting how your knowledge can
probably translate to decent guesswork.)_

The following wire panels are affected:
**Electrical Engineering:**
- APCs
- Cameras
- IFF Beacons
- Radios
- Smartfridges
- SMES Units

**Mechanical Engineering**
- Airlocks
- Disposal Units
- Fabricators
- Vending Machines

**Atmospherics Systems**
- Air Alarms

**Reactor Systems**
- Particle Accelerator Control Boxes (lol)

**Robotics**
- Hardsuits
- Suit Storage Units (sharing the love is all)
- Robots
- Tag Scanners

**Xenobiology**
- Stasis Cages

Also, I made it possible to blow out all the lights in an APC's area by
snipping the power regulator cable and then pulsing the lights wire.
Great for signalers.

Speaking of signalers, new app deployed to all Engineering, Research,
and Robotics personal modular computers:
<img width="816" height="722" alt="Screenshot 2026-07-14 144049"
src="https://github.com/user-attachments/assets/3d588712-ebfd-47ac-b699-7cdac2c04907"
/>

Self-explanatory. Please only use corporate-provided software for
behavior within your contract regulations.

code/game/objects/items/devices/PDA/radio.dm

@@ -44,8 +44,12 @@
 	var/frequency = 1457
 	var/code = 30.0
 	var/last_transmission
+	var/listening = TRUE
 	var/datum/radio_frequency/radio_connection
 
+/obj/item/integrated_signaler/signal/network_card
+	listening = FALSE
+
 /obj/item/integrated_signaler/signal/Initialize()
 	. = ..()
 	if(!SSradio)
@@ -57,26 +61,83 @@
 	set_frequency(frequency)
 
 /obj/item/integrated_signaler/signal/proc/set_frequency(new_frequency)
-	SSradio.remove_object(src, frequency)
-	frequency = new_frequency
-	radio_connection = SSradio.add_object(src, frequency)
+	if(!SSradio || !new_frequency)
+		return FALSE
+	var/sanitized_frequency = sanitize_frequency(new_frequency, RADIO_LOW_FREQ, RADIO_HIGH_FREQ)
+	if(sanitized_frequency > RADIO_HIGH_FREQ)
+		sanitized_frequency = RADIO_HIGH_FREQ - 1
+	if(radio_connection && frequency == sanitized_frequency)
+		return TRUE
+	if(radio_connection)
+		SSradio.remove_object(src, frequency)
+	frequency = sanitized_frequency
+	if(listening)
+		radio_connection = SSradio.add_object(src, frequency)
+	else
+		radio_connection = null
+	return TRUE
 
-/obj/item/integrated_signaler/signal/proc/send_signal(message="ACTIVATE")
+/obj/item/integrated_signaler/signal/proc/set_listening(var/new_listening)
+	new_listening = !!new_listening
+	if(listening == new_listening)
+		return TRUE
+
+	listening = new_listening
+	if(listening)
+		return set_frequency(frequency)
+
+	if(radio_connection)
+		SSradio.remove_object(src, frequency)
+	radio_connection = null
+	return TRUE
+
+/obj/item/integrated_signaler/signal/proc/send_signal(message="ACTIVATE", var/mob/user)
+	if(!SSradio)
+		return FALSE
+	var/datum/radio_frequency/transmit_connection = radio_connection
+	if(!transmit_connection)
+		transmit_connection = SSradio.return_frequency(frequency)
+	if(!transmit_connection)
+		return FALSE
+	if(within_jamming_range(src))
+		return FALSE
 	if(last_transmission && world.time < (last_transmission + 5))
-		return
+		return FALSE
 	last_transmission = world.time
 
 	var/time = time2text(world.realtime,"hh:mm:ss")
 	var/turf/T = get_turf(src)
-	GLOB.lastsignalers.Add("[time] <B>:</B> [usr.key] used [src] @ location ([T.x],[T.y],[T.z]) <B>:</B> [format_frequency(frequency)]/[code]")
+	var/user_key = user ? user.key : usr?.key
+	GLOB.lastsignalers.Add("[time] <B>:</B> [user_key ? user_key : "userless"] used [src] @ location ([T ? T.x : 0],[T ? T.y : 0],[T ? T.z : 0]) <B>:</B> [format_frequency(frequency)]/[code]")
 
 	var/datum/signal/signal = new
 	signal.source = src
 	signal.encryption = code
 	signal.data["message"] = message
+	if(user)
+		signal.data["user"] = WEAKREF(user)
 
-	radio_connection.post_signal(src, signal)
+	transmit_connection.post_signal(src, signal)
+	return TRUE
+
+/obj/item/integrated_signaler/signal/receive_signal(var/datum/signal/signal)
+	if(!signal)
+		return FALSE
+	if(signal.source == src)
+		return FALSE
+	if(signal.data["message"] != "ACTIVATE")
+		return FALSE
+	if(isnull(signal.encryption))
+		return FALSE
+	if(within_jamming_range(src))
+		return FALSE
+
+	var/obj/item/computer_hardware/network_card/network_card = loc
+	if(istype(network_card))
+		return network_card.receive_signaler_signal(src, signal)
+	return FALSE
 
 /obj/item/integrated_signaler/signal/Destroy()
-	SSradio.remove_object(src, frequency)
+	if(SSradio)
+		SSradio.remove_object(src, frequency)
 	return ..()