Should fix hallucinations being permanent (#3445)

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## About The Pull Request

Fixes #3435

Caps hallucination natural decay at 0 so it can't reach negative numbers
off dumb stuff and never actually stop doing stuff

## Changelog

:cl:
fix: hallucinations can no longer be permanent unless treated
/:cl:

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Signed-off-by: Theos <[email protected]>

code/modules/flufftext/Hallucination.dm

@@ -29,7 +29,7 @@ GLOBAL_LIST_INIT(hallucination_list, list(
 	if(!hallucination)
 		return
 
-	hallucination--
+	hallucination = max(hallucination - 1, 0)
 
 	if(world.time < next_hallucination)
 		return