It appears that the repository has undergone several changes and renamings:

backend/node_modules/tailwindcss/plugin.d.ts

@@ -1,11 +0,0 @@
-import type { Config, PluginCreator } from './types/config'
-type Plugin = {
-  withOptions<T>(
-    plugin: (options: T) => PluginCreator,
-    config?: (options: T) => Partial<Config>
-  ): { (options: T): { handler: PluginCreator; config?: Partial<Config> }; __isOptionsFunction: true }
-  (plugin: PluginCreator, config?: Partial<Config>): { handler: PluginCreator; config?: Partial<Config> }
-}
-
-declare const plugin: Plugin
-export = plugin