docs: remove product switcher from docs nav (#272)

The docs site nav carried a "Products" dropdown listing both ktx and
the legacy Kaelio agent platform. On the ktx docs, a co-equal product
switcher framed ktx as one of two products and gave the unrelated
legacy product equal billing. Remove it so the ktx docs stay focused;
cross-product discovery belongs at the docs.kaelio.com apex, not in the
ktx nav.

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

docs-site/app/layout.config.tsx

@@ -8,23 +8,6 @@ export const baseOptions: BaseLayoutProps = {
     transparentMode: "top",
   },
   links: [
-    {
-      type: "menu",
-      text: "Products",
-      items: [
-        {
-          text: "ktx",
-          description: "The ktx CLI & toolkit docs",
-          url: "/docs",
-        },
-        {
-          text: "Kaelio Platform",
-          description: "Docs for the Kaelio platform",
-          url: "https://docs.kaelio.com/agent/docs",
-          external: true,
-        },
-      ],
-    },
     {
       type: "icon",
       label: "Join the ktx Slack community",