Adds the Family Heirloom, Nyctophobia, and Monochromacy traits, and rebalances Social Anxiety (#36426)

* Adds some more traits

* April Fools' heirlooms

* Fixes the detective sound

* Refactor to use signals

code/modules/client/client_colour.dm

@@ -105,4 +105,9 @@
 	colour = "#ff99ff"
 
 /datum/client_colour/glass_colour/gray
-	colour = "#cccccc"
+	colour = "#cccccc"
+
+
+/datum/client_colour/monochrome
+	colour = list(rgb(77,77,77), rgb(150,150,150), rgb(28,28,28), rgb(0,0,0))
+	priority = INFINITY //we can't see colors anyway!