feat: add entry types

Author: pengzhanbo

lib/index.d.ts

@@ -0,0 +1,7 @@
+import type { Extends, Plugins, RuleOptions } from './types'
+
+declare module 'stylelint-define-config' {
+  export interface CustomPlugins extends Plugins { }
+  export interface CustomExtends extends Extends { }
+  export interface CustomRuleOptions extends RuleOptions { }
+}