landing: update dive-in link text to 'View the end-to-end MPCP flow'

Made-with: Cursor

Author: NAOR YUVAL

index.html

@@ -329,7 +329,7 @@ <h2>How MPCP works</h2>
       </div>
       <p>MPCP represents machine payments as a chain of signed authorization artifacts.</p>
       <p><strong>MPCP is to machine payments what OAuth is to API authorization.</strong></p>
-      <a href="/spec/architecture/reference-flow/" class="dive-in">Dive in → Reference flow</a>
+      <a href="/spec/architecture/reference-flow/" class="dive-in">View the end-to-end MPCP flow →</a>
     </section>
 
     <section>