refactor: centralize feed handler creation, use typed route props

app/feed.xml/route.ts

@@ -1,13 +1,3 @@
-import { NextResponse } from "next/server";
+import { createFeedHandler } from "@/lib/build-feed";
 
-import { buildFeed } from "@/lib/build-feed";
-
-export const GET = () => {
-  const feed = buildFeed();
-
-  return new NextResponse(feed.rss2(), {
-    headers: {
-      "content-type": "application/rss+xml; charset=utf-8",
-    },
-  });
-};
+export const { GET } = createFeedHandler("rss");