chore: make recreateServer optional (#1165)

src/node/plugin.ts

@@ -257,7 +257,7 @@ export async function createVitePressPlugin(
         )
         try {
           clearCache()
-          await recreateServer!()
+          await recreateServer?.()
         } catch (err) {
           console.error(c.red(`failed to restart server. error:\n`), err)
         }

src/node/server.ts

@@ -5,7 +5,7 @@ import { createVitePressPlugin } from './plugin'
 export async function createServer(
   root: string = process.cwd(),
   serverOptions: ServerOptions = {},
-  recreateServer: () => Promise<void>
+  recreateServer?: () => Promise<void>
 ) {
   const config = await resolveConfig(root)