feat(Navbar): hide navigation on /blog routes

Hide navbar by default on /blog and its subpaths

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Co-Authored-By: Claude <noreply@anthropic.com>

dashboard/src/components/Navbar.tsx

@@ -28,7 +28,7 @@ type NavSubItem = {
 export default function Navbar() {
   const pathname = usePathname()
   const isHiddenRoute = pathname
-    ? ['/login', '/register', '/xstream', '/xcloudflow', '/xscopehub'].some((prefix) =>
+    ? ['/login', '/register', '/xstream', '/xcloudflow', '/xscopehub', '/blog'].some((prefix) =>
         pathname.startsWith(prefix),
       )
     : false