docs: update registry agents (#494)

Co-authored-by: benbrandt <2111074+benbrandt@users.noreply.github.com>

Author: acp-release-bot[bot]

docs/get-started/registry.mdx

@@ -239,7 +239,7 @@ Visit [the registry repository on GitHub](https://github.com/agentclientprotocol
   </Card>
   <Card
     title="OpenCode"
-    href="https://github.com/sst/opencode"
+    href="https://github.com/anomalyco/opencode"
     icon={
       <svg width="20" height="20" className="agent-icon" aria-hidden="true" focusable="false" viewBox="0 0 16 16" fill="none" xmlns="http://www.w3.org/2000/svg">
       <path fillRule="evenodd" clipRule="evenodd" d="M13 14H3V2H13V14ZM10.5 4.4H5.5V11.6H10.5V4.4Z" fill="currentColor"/>
@@ -273,6 +273,19 @@ Visit [the registry repository on GitHub](https://github.com/agentclientprotocol
       <code>0.10.1</code>
     </p>
   </Card>
+  <Card
+    title="Stakpak"
+    href="https://github.com/stakpak/agent"
+    icon={
+      <svg width="20" height="20" className="agent-icon" aria-hidden="true" focusable="false" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 16 16">
+        <path fill="currentColor" d="M6.53 4.412h5.883v3.587H9.471v3.588H3.588V7.999H6.53Z"/>
+      </svg>
+    }
+  >
+    <p class="text-xs mt-3">
+      <code>0.3.38</code>
+    </p>
+  </Card>
 </CardGroup>
 
 ## Using the Registry