feat(web): add CrawlProof ad unit to /blog/*

Reusable AdUnit component (div[data-cp-ad] + ad.js via next/script) placed
in-content on the blog index and post pages, scoped to /blog/* only.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

apps/logicsrc-web/src/components/ad-unit.tsx

@@ -0,0 +1,20 @@
+import type { ReactNode } from "react";
+import Script from "next/script";
+
+// CrawlProof ad unit, scoped to the pages that render it (currently /blog/*).
+// The loader is deduped by src, so mounting <AdUnit /> on multiple routes only
+// injects one https://crawlproof.com/ad.js.
+export function AdUnit({
+  slot,
+  format = "banner_300x250",
+}: {
+  slot: string;
+  format?: string;
+}): ReactNode {
+  return (
+    <>
+      <div data-cp-ad data-slot={slot} data-format={format} />
+      <Script src="https://crawlproof.com/ad.js" strategy="afterInteractive" />
+    </>
+  );
+}