Update official links to use json-render.dev domain (#265)

* Update official links to use json-render.dev domain

- Change dashboard example Docs link from json-render.vercel.app to json-render.dev
- Change Svelte Chat demo URL from json-render-svelte-chat-demo.labs.vercel.dev to svelte-chat-demo.json-render.dev

Fixes #264

* Revert svelte-chat demo URL change

Keep the original labs.vercel.dev URL for the Svelte Chat demo.

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Co-authored-by: ctate <366502+ctate@users.noreply.github.com>

examples/dashboard/components/header.tsx

@@ -47,7 +47,7 @@ export function Header() {
         </div>
         <nav className="flex items-center gap-4">
           <a
-            href="https://json-render.vercel.app"
+            href="https://json-render.dev"
             target="_blank"
             rel="noopener noreferrer"
             className="text-sm text-muted-foreground hover:text-foreground transition-colors"