Add dialogue portrait slots

scripts/core/battle_state.gd

@@ -2487,14 +2487,15 @@ func _normalize_dialogue_line(line) -> Dictionary:
 		var text := str(line)
 		if text.is_empty():
 			return {}
-		return {"speaker": "", "text": text}
+		return {"speaker": "", "text": text, "portrait": ""}
 	if typeof(line) == TYPE_DICTIONARY:
 		var text := str(line.get("text", ""))
 		if text.is_empty():
 			return {}
 		return {
 			"speaker": str(line.get("speaker", "")),
-			"text": text
+			"text": text,
+			"portrait": str(line.get("portrait", ""))
 		}
 	return {}