Weapons that cannot fit into turrets also cannot fit into emitters. (#90960)

## About The Pull Request
fixes https://github.com/tgstation/tgstation/issues/90260

Weapons that cannot fit into turrets can not fit into emitters. This
only affects the dueling pistol as of writing.

## Why It's Good For The Game

Sorry everyone, this is TOO fun, we have to turn it around.

## Changelog
🆑
fix: Weapons that cannot fit into turrets also cannot fit into emitters.
/🆑

code/modules/power/singularity/emitter.dm

@@ -356,6 +356,9 @@
 		return
 	if(!user.transferItemToLoc(energy_gun, src))
 		return
+	if(energy_gun.gun_flags & TURRET_INCOMPATIBLE)
+		user.balloon_alert(user, "[energy_gun] won't fit!")
+		return
 	gun = energy_gun
 	gun_properties = gun.get_turret_properties()
 	set_projectile()