feat(type): expose the Plugin type (#1264)

* feat(type): expose the Plugin type

* chore(ci): [bot] format code

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Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

Author: Sunny-117

src/index.ts

@@ -30,8 +30,9 @@ import { runTypeScriptCompiler } from './tsc'
 import { runDtsRollup } from './api-extractor'
 import { cjsInterop } from './plugins/cjs-interop'
 import type { Format, KILL_SIGNAL, NormalizedOptions, Options } from './options'
+import type { Plugin } from './plugin'
 
-export type { Format, Options, NormalizedOptions }
+export type { Format, Options, NormalizedOptions, Plugin }
 
 export const defineConfig = (
   options: