feat: add 'Open in StackBlitz' button to header (#10)

packages/bolt/app/components/header/Header.tsx

@@ -0,0 +1,15 @@
+import { ClientOnly } from 'remix-utils/client-only';
+import { OpenStackBlitz } from './OpenStackBlitz.client';
+
+export function Header() {
+  return (
+    <header className="flex items-center bg-white p-4 border-b border-gray-200 h-[var(--header-height)]">
+      <div className="flex items-center gap-2">
+        <div className="text-2xl font-semibold text-accent">Bolt</div>
+      </div>
+      <div className="ml-auto">
+        <ClientOnly>{() => <OpenStackBlitz />}</ClientOnly>
+      </div>
+    </header>
+  );
+}