Farm Sounds DLC (basic mobs can make sounds when speaking) (#74906)

## About The Pull Request

https://user-images.githubusercontent.com/66640614/233747544-aac153b9-a100-486c-9a7a-4a436b8303b8.mov

Cows, pigs, and sheep make noise when their AI makes them speak. 
~~Also House Flipper Farm DLC came out but that's incidental.~~

## Why It's Good For The Game
It's funny, also more sound effects are fun. Gives basic mob creators
more customizability.

## Changelog
🆑 Tattle
qol: basicmobs can now make sounds when their speech is triggered
qol: pigs will now make sounds and emote on their own
sound: cows, pigs, and sheep have new sound effects!
/🆑

---------

Co-authored-by: tattle <article.disaster@gmail.com>
Co-authored-by: MrMelbert <51863163+MrMelbert@users.noreply.github.com>

code/datums/ai/basic_mobs/basic_subtrees/speech_subtree.dm

@@ -7,11 +7,15 @@
 	var/list/emote_see = list()
 	///Possible lines of speech the AI can have
 	var/list/speak = list()
+	///The sound effects associated with this speech, if any
+	var/list/sound = list()
 
 /datum/ai_planning_subtree/random_speech/New()
 	. = ..()
 	if(speak)
 		speak = string_list(speak)
+	if(sound)
+		sound = string_list(sound)
 	if(emote_hear)
 		emote_hear = string_list(emote_hear)
 	if(emote_see)
@@ -32,7 +36,7 @@
 		else if(random_number_in_range <= (audible_emotes_length + non_audible_emotes_length))
 			controller.queue_behavior(/datum/ai_behavior/perform_emote, pick(emote_see))
 		else
-			controller.queue_behavior(/datum/ai_behavior/perform_speech, pick(speak))
+			controller.queue_behavior(/datum/ai_behavior/perform_speech, pick(speak), length(sound) > 0 ? pick(sound) : null)
 
 /datum/ai_planning_subtree/random_speech/insect
 	speech_chance = 5
@@ -55,6 +59,7 @@
 /datum/ai_planning_subtree/random_speech/sheep
 	speech_chance = 5
 	speak = list("baaa","baaaAAAAAH!","baaah")
+	sound = list('sound/creatures/sheep1.ogg', 'sound/creatures/sheep2.ogg', 'sound/creatures/sheep3.ogg')
 	emote_hear = list("bleats.")
 	emote_see = list("shakes her head.", "stares into the distance.")
 
@@ -83,6 +88,7 @@
 /datum/ai_planning_subtree/random_speech/cow
 	speech_chance = 1
 	speak = list("moo?","moo","MOOOOOO")
+	sound = list('sound/creatures/cow.ogg')
 	emote_hear = list("brays.")
 	emote_see = list("shakes her head.")
 
@@ -93,6 +99,7 @@
 /datum/ai_planning_subtree/random_speech/cow/wisdom/New()
 	. = ..()
 	speak = GLOB.wisdoms //Done here so it's setup properly
+	sound = list()
 
 /datum/ai_planning_subtree/random_speech/dog
 	speech_chance = 1
@@ -120,3 +127,10 @@
 /datum/ai_planning_subtree/random_speech/tree
 	speech_chance = 3
 	emote_see = list("photosynthesizes angirly.")
+
+/datum/ai_planning_subtree/random_speech/pig
+	speech_chance = 3
+	speak = list("oink?","oink","snurf")
+	sound = list('sound/creatures/pig1.ogg', 'sound/creatures/pig2.ogg')
+	emote_hear = list("snorts.")
+	emote_see = list("sniffs around.")