Update structure to domain driven architecture.

web/responses.go

@@ -0,0 +1,18 @@
+package web
+
+type ErrorResponse struct {
+	Error string `json:"error"`
+}
+
+type SuccessResponse struct {
+	Message string `json:"message"`
+}
+
+type AuthResponse struct {
+	AccessToken  string `json:"access_token"`
+	RefreshToken string `json:"refresh_token"`
+}
+
+type RefreshTokenReq struct {
+	RefreshToken string `json:"refresh_token"`
+}