revert!: sync defineConfig types with vite (#2529)

BREAKING CHANGE: reverts the breaking changes in beta-2

Author: brc-dd

src/node/config.ts

@@ -38,15 +38,15 @@ export type UserConfigExport<ThemeConfig> =
 /**
  * Type config helper
  */
-export function defineConfig(config: UserConfigExport<DefaultTheme.Config>) {
+export function defineConfig(config: UserConfig<DefaultTheme.Config>) {
   return config
 }
 
 /**
  * Type config helper for custom theme config
  */
 export function defineConfigWithTheme<ThemeConfig>(
-  config: UserConfigExport<ThemeConfig>
+  config: UserConfig<ThemeConfig>
 ) {
   return config
 }