Add Emitter Emissives (#95270)

## About The Pull Request

Add an emissive overlay for the lights on emitters

## Why It's Good For The Game

<img width="285" height="218" alt="image"
src="https://github.com/user-attachments/assets/372f5b1b-61ed-4627-a189-577ec3aac264"
/>
<img width="275" height="234" alt="image"
src="https://github.com/user-attachments/assets/5959ac90-4856-427b-ab29-f1cbeb68422a"
/>


cool

## Changelog
🆑
image: emitters glow in the dark now
/🆑

code/modules/power/singularity/emitter.dm

@@ -157,6 +157,7 @@
 	var/mutable_appearance/overlay = mutable_appearance(icon, "emitter_overlay")
 	overlay.color = laser_color
 	. += overlay
+	. += emissive_appearance(icon, "emitter_overlay", src, alpha = src.alpha)
 
 /obj/machinery/power/emitter/update_icon_state()
 	if(panel_open)