Adds CI to restrict types in a file (#24694)

* LETS GAMBLE!

* oops

* even more oops

* alright lets fuckin do it

* real names please

* comment

* Contributing.md update

* maybe someone will find this todo

* actually lets make it a define so people can't mistype it

* review

* changes

code/__DEFINES/antag_defines.dm

@@ -61,3 +61,10 @@ GLOBAL_LIST(contractors)
  * Pulse Demon
  */
 #define PULSEDEMON_SOURCE_DRAIN_INVALID (-1)
+
+/proc/ischangeling(mob/M) // TODO: Someone please convert these to proper defines some day.
+	return M.mind?.has_antag_datum(/datum/antagonist/changeling)
+
+// Helper proc that determines if a mob is a mindslave.
+/proc/ismindslave(mob/living/carbon/human/H)
+	return istype(H) && H.mind.has_antag_datum(/datum/antagonist/mindslave, FALSE)

code/__DEFINES/misc_defines.dm

@@ -695,3 +695,6 @@ do { \
 #define TEAM_ADMIN_ADD_OBJ_SUCCESS				(1<<0)
 #define TEAM_ADMIN_ADD_OBJ_CANCEL_LOG 			(1<<1)
 #define TEAM_ADMIN_ADD_OBJ_PURPOSEFUL_CANCEL 	(1<<2)
+
+/// A helper used by `restrict_file_types.py` to identify types to restrict in a file. Not used by byond at all.
+#define RESTRICT_TYPE(type) // do nothing