Make headers accessible in the reroute hook

Author: Stadly

packages/kit/src/runtime/server/respond.js

@@ -114,8 +114,11 @@ export async function respond(request, options, manifest, state) {
 	let resolved_path;
 
 	try {
-		// reroute could alter the given URL, so we pass a copy
-		resolved_path = options.hooks.reroute({ url: new URL(url) }) ?? url.pathname;
+		// reroute could alter the given data, so we pass copies
+		resolved_path = options.hooks.reroute({
+			url: new URL(url),
+			headers: new Headers(request.headers),
+		}) ?? url.pathname;
 	} catch {
 		return text('Internal Server Error', {
 			status: 500