Add multiplex ads to the homepage and update ad component

Add a new `MultiplexAd` component and integrate it into the homepage, also update the `AdSense` component's `AdFormat` type to include "autorelaxed".

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client/src/components/adsense.tsx

@@ -1,6 +1,6 @@
 import { useEffect, useRef } from "react";
 
-type AdFormat = "auto" | "fluid" | "rectangle" | "horizontal" | "vertical";
+type AdFormat = "auto" | "fluid" | "rectangle" | "horizontal" | "vertical" | "autorelaxed";
 
 interface AdSenseProps {
   slot: string;
@@ -77,6 +77,19 @@ export function InArticleAd() {
   );
 }
 
+export function MultiplexAd() {
+  return (
+    <div className="bg-card rounded-md border border-card-border overflow-hidden">
+      <AdSense
+        slot="4593001335"
+        format="autorelaxed"
+        style={{ display: "block" }}
+        className="w-full min-h-[250px]"
+      />
+    </div>
+  );
+}
+
 export function SidebarAd() {
   return (
     <div className="bg-card rounded-md border border-card-border p-4 mt-6">