use gauss elimination for color matrix (#19190)

* use gauss elimination for color matrix

* .

* Update functions.ts

* Update functions.ts

* some more improvements

* .

* .

* .

* ugh

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Co-authored-by: Cameron Lennox <killer65311@gmail.com>

code/modules/hydroponics/spreading/spreading_growth.dm

@@ -111,6 +111,8 @@
 					sleep(rand(3,5))
 					if(!length(neighbors))
 						break
+					if(QDELETED(src)) // we sleep, might get deleted!
+						return
 					spread_to(pick(neighbors))
 
 	// We shouldn't have spawned if the controller doesn't exist.