fix: replace usage of fromEntries in browser bundled resolve-rewrites.ts (#25208)

## Bug

- [x] Related issues linked using `fixes #number`
- [ ] Integration tests added

Fixes #25207

Currently rewritten routes that use a `has` condition throw an `Object.fromEntries is not a function` error in older browsers.

## Documentation / Examples

- [x] Make sure the linting passes

## Solution

As mentioned in issue #25207, looks like last year the team decided not to include the `fromEntries` polyfill #15772 (comment).

As such, we should avoid using non-polyfilled methods in core next.js code bundled in the browser.

This PR's changes should result in the same object being returned, without using `fromEntries`.

Author: jamsinclair

packages/next/next-server/lib/router/utils/resolve-rewrites.ts

@@ -43,12 +43,13 @@ export default function resolveRewrites(
           headers: {
             host: document.location.hostname,
           },
-          cookies: Object.fromEntries(
-            document.cookie.split('; ').map((item) => {
+          cookies: document.cookie
+            .split('; ')
+            .reduce<Record<string, string>>((acc, item) => {
               const [key, ...value] = item.split('=')
-              return [key, value.join('=')]
-            })
-          ),
+              acc[key] = value.join('=')
+              return acc
+            }, {}),
         } as any,
         rewrite.has,
         parsedAs.query