fix: replace wallet-sdk links with gateway-client on landing page (#2)

Wallet SDK is archived; mpcp-gateway-client is the recommended agent SDK.
Updates the Explore CTA card and footer link.

Made-with: Cursor

Co-authored-by: NAOR YUVAL <naoryuval@NAORs-MacBook-Air.local>

Author: naory

index.html

@@ -361,9 +361,9 @@ <h2>Explore</h2>
           <strong>Trust Gateway</strong>
           <span>Budget enforcement, x402, signed receipts</span>
         </a>
-        <a href="https://github.com/mpcp-protocol/mpcp-wallet-sdk">
-          <strong>Wallet SDK</strong>
-          <span>Agent wallet, React hooks, session management</span>
+        <a href="https://github.com/mpcp-protocol/mpcp-gateway-client">
+          <strong>Gateway Client</strong>
+          <span>session.fetch(), framework adapters, receipts</span>
         </a>
       </div>
     </section>
@@ -374,7 +374,7 @@ <h2>Explore</h2>
     <a href="https://github.com/mpcp-protocol/mpcp-spec">Spec</a> · 
     <a href="https://github.com/mpcp-protocol/mpcp-reference">Reference</a> · 
     <a href="https://github.com/mpcp-protocol/mpcp-gateway">Gateway</a> · 
-    <a href="https://github.com/mpcp-protocol/mpcp-wallet-sdk">Wallet SDK</a>
+    <a href="https://github.com/mpcp-protocol/mpcp-gateway-client">Gateway Client</a>
   </footer>
 </body>
 </html>