SMES units made explosion proof (#7402)

# About the pull request

SMES can be exploaded to be removed unlike any other of main intel
objectives, that is not unitended as they can not be repaired or rebuild
in any way

# Explain why it's good for the game

intel objectives are not ment to be removeable, especialy such a big
one, also no SMES mean no lights on colony and stuff them being
removable is unintentional


# Testing Photographs and Procedure
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<summary>Screenshots & Videos</summary>

Put screenshots and videos here with an empty line between the
screenshots and the `<details>` tags.

</details>


# Changelog
:cl:
fix: SMES units made explosion proof
/:cl:

---------

Co-authored-by: vincibrv <[email protected]>

code/modules/power/smes.dm

@@ -39,6 +39,7 @@
 	var/building_terminal = 0 //Suggestions about how to avoid clickspam building several terminals accepted!
 	var/should_be_mapped = 0 // If this is set to 0 it will send out warning on New()
 	power_machine = TRUE
+	var/explosion_proof = TRUE
 
 /obj/structure/machinery/power/smes/Initialize()
 	. = ..()
@@ -62,6 +63,12 @@
 
 	return INITIALIZE_HINT_ROUNDSTART
 
+/obj/structure/machinery/power/smes/ex_act(severity)
+	if(explosion_proof)
+		return
+	else
+		.=..()
+
 /obj/structure/machinery/power/smes/LateInitialize()
 	. = ..()