增加对于生成的导出变量的记录。

src/material-3-scheme.ts

@@ -54,4 +54,7 @@ export type MaterialDesign3SchemeSource = {
 export type MaterialDesign3SchemeStorage = {
   source?: MaterialDesign3SchemeSource;
   scheme?: MaterialDesign3Scheme;
+  cssVariables?: string;
+  scssVariables?: string;
+  jsVariables?: string;
 };