docs: TopBar override to mention open-in-stackblitz-link slot (#324)

Author: AriPerkkio

docs/tutorialkit.dev/astro.config.ts

@@ -13,6 +13,11 @@ export default defineConfig({
       'Cross-Origin-Opener-Policy': 'same-origin',
     },
   },
+  vite: {
+    ssr: {
+      noExternal: '@tutorialkit/react',
+    },
+  },
   integrations: [
     react(),
     UnoCSS(),

docs/tutorialkit.dev/src/content/docs/guides/overriding-components.mdx

@@ -44,6 +44,7 @@ tutorialkit({
 When overriding `TopBar` you can place TutorialKit's default components using following [Astro slots](https://docs.astro.build/en/basics/astro-components/#named-slots):
 
 - `logo`: Logo of the application
+- `open-in-stackblitz-link`: Link for opening current lesson in StackBlitz
 - `theme-switch`:  Switch for changing the theme
 - `login-button`: For StackBlitz Enterprise user, the login button
 
@@ -59,6 +60,8 @@ When overriding `TopBar` you can place TutorialKit's default components using fo
 
   <LanguageSelect />
 
+  <slot name="open-in-stackblitz-link" />
+
   <slot name="login-button" />
 </nav>
 ```