fix(next): update rest route handler types for Next.js 15.5 compatibility

packages/next/src/routes/rest/index.ts

@@ -9,7 +9,7 @@ const handlerBuilder =
   async (
     request: Request,
     args: {
-      params: Promise<{ slug: string[] }>
+      params: Promise<{ slug?: string[] }>
     },
   ): Promise<Response> => {
     const awaitedConfig = await config

templates/website/src/app/(frontend)/next/preview/route.ts

@@ -3,18 +3,11 @@ import { getPayload } from 'payload'
 
 import { draftMode } from 'next/headers'
 import { redirect } from 'next/navigation'
+import { NextRequest } from "next/server"
 
 import configPromise from '@payload-config'
 
-export async function GET(
-  req: {
-    cookies: {
-      get: (name: string) => {
-        value: string
-      }
-    }
-  } & Request,
-): Promise<Response> {
+export async function GET(req: NextRequest): Promise<Response> {
   const payload = await getPayload({ config: configPromise })
 
   const { searchParams } = new URL(req.url)

templates/with-vercel-website/src/app/(frontend)/next/preview/route.ts

@@ -3,18 +3,11 @@ import { getPayload } from 'payload'
 
 import { draftMode } from 'next/headers'
 import { redirect } from 'next/navigation'
+import { NextRequest } from "next/server"
 
 import configPromise from '@payload-config'
 
-export async function GET(
-  req: {
-    cookies: {
-      get: (name: string) => {
-        value: string
-      }
-    }
-  } & Request,
-): Promise<Response> {
+export async function GET(req: NextRequest): Promise<Response> {
   const payload = await getPayload({ config: configPromise })
 
   const { searchParams } = new URL(req.url)