Added chat microservice, removed air

chat-service/serializer/serializer.go

@@ -0,0 +1,8 @@
+package serializer
+
+import "twitch-clone/chat-service/models"
+
+type MessageSerializer interface {
+	Decode(input []byte) (*models.ChatMessage, error)
+	Encode(input *models.ChatMessage) ([]byte, error)
+}