TTS fixes + Megaphone (#24)

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# About the pull request
TTS fixes + Megaphone
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:cl:
fix: TTS fixes + Megaphone
/:cl:

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## Summary by Sourcery

Reduce stamina, oxygen, and brain damage from speech filter, and add TTS
to megaphone broadcasts.

New Features:
- Added TTS support for megaphone broadcasts.

Bug Fixes:
- Fixed an issue where the speech filter caused excessive stamina,
oxygen, and brain damage.

code/game/objects/items/devices/megaphone.dm

@@ -49,6 +49,7 @@
 			if(!ishumansynth_strict(listener) && !isobserver(listener))
 				listener.show_message("[user] says something on the microphone, but you can't understand it.")
 				continue
+			user.cast_tts(listener, message, user, TRUE, 4)	// SS220 ADD - TTS
 			listener.show_message("<B>[user]</B> broadcasts, [FONT_SIZE_LARGE("\"[message]\"")]", SHOW_MESSAGE_AUDIBLE) // 2 stands for hearable message
 			langchat_long_listeners += listener
 		playsound(loc, 'sound/items/megaphone.ogg', 100, FALSE, TRUE)

modular/text_to_speech/code/hear.dm

@@ -11,7 +11,7 @@
 		return
 	if(!say_understands(speaker, language))
 		return
-	speaker.cast_tts(src, message, src, FALSE, null, null)
+	speaker.cast_tts(src, message)
 
 /mob/hear_radio(
 	message, verb="says",