Adds CI to forbid some istype(src) checks. (#26980)

* first set of changes

* the last checks

* actually builds

* Update code/modules/surgery/organs/subtypes/standard_organs.dm

Co-authored-by: Luc <89928798+lewcc@users.noreply.github.com>
Signed-off-by: Contrabang <91113370+Contrabang@users.noreply.github.com>

* Update tools/ci/check_grep2.py

Signed-off-by: Contrabang <91113370+Contrabang@users.noreply.github.com>

* 1 fix (cigarettes) and better encapsulation in files

* yeeep

---------

Signed-off-by: Contrabang <91113370+Contrabang@users.noreply.github.com>
Co-authored-by: Luc <89928798+lewcc@users.noreply.github.com>

code/game/objects/effects/decals/Cleanable/humans.dm

@@ -55,7 +55,7 @@
 	var/turf/T = get_turf(src)
 	check_gravity(T)
 
-	if(!istype(src, /obj/effect/decal/cleanable/blood/footprints) && ((T && (T.density)) || !gravity_check || locate(/obj/structure/window/full) in T || locate(/obj/structure/grille/) in T))
+	if(should_be_off_floor())
 		off_floor = TRUE
 		layer = ABOVE_MOB_LAYER
 		plane = GAME_PLANE
@@ -85,6 +85,10 @@
 		overlays.Cut()
 	..()
 
+/obj/effect/decal/cleanable/blood/proc/should_be_off_floor()
+	var/turf/T = get_turf(src)
+	return ((T && T.density) || !gravity_check || (locate(/obj/structure/window/full) in T) || (locate(/obj/structure/grille) in T))
+
 /obj/effect/decal/cleanable/blood/proc/dry()
 	name = dryname
 	desc = drydesc

code/game/objects/effects/decals/Cleanable/tracks.dm

@@ -123,6 +123,9 @@ GLOBAL_LIST_EMPTY(fluidtrack_cache)
 
 	alpha = base_alpha + bloodiness
 
+/obj/effect/decal/cleanable/blood/footprints/should_be_off_floor()
+	return FALSE
+
 /proc/createFootprintsFrom(atom/movable/A, dir, turf/T)
 	var/obj/effect/decal/cleanable/blood/footprints/FP = new /obj/effect/decal/cleanable/blood/footprints(T)
 	if(ishuman(A))