improve detection and update docs

Author: yannbf

README.md

@@ -3,7 +3,7 @@
 Storybook test runner turns all of your stories into executable tests.
 
 > [!WARNING]  
-> If you're using Storybook in a Vite-based project, you might want to use [Storybook's Vitest integration](https://storybook.js.org/docs/writing-tests/integrations/vitest-addon?ref=test-runner-migration) instead. It's faster, provides features out of the box such as a11y and coverage, and integrates well with all Storybook's latest features.
+> If you're using Storybook in a Vite-based project, you might want to use [Storybook's Vitest integration](https://storybook.js.org/docs/writing-tests/integrations/vitest-addon?ref=test-runner-migration) instead. It's faster, provides features out of the box such as a11y and coverage, and integrates well with all Storybook's latest features. [Read the migration steps here](https://storybook.js.org/docs/writing-tests/integrations/vitest-addon/migration-guide).
 
 <h2>Table of Contents</h2>
 

src/test-storybook.ts

@@ -424,10 +424,13 @@ const main = async () => {
   const { storiesPaths, lazyCompilation, disableTelemetry, enableCrashReports, frameworkName } =
     await getStorybookMetadata();
 
-  if (frameworkName.includes('vite')) {
+  const shouldMigrateToVitest =
+    frameworkName.includes('vite') || frameworkName.includes('sveltekit');
+
+  if (shouldMigrateToVitest) {
     warnOnce(
-      'Detected Vite-based Storybook project, you might benefit from migrating to the Vitest addon, a modern, faster and more feature-rich testing solution for Storybook: https://storybook.js.org/docs/writing-tests/integrations/vitest-addon?ref=test-runner-migration'
-    );
+      'Detected Vite-based Storybook project, you might benefit from migrating to the Vitest addon, a modern, faster and more feature-rich testing solution for Storybook:\nhttps://storybook.js.org/docs/writing-tests/integrations/vitest-addon/migration-guide?ref=test-runner-migration'
+    )();
   }
 
   if (!shouldRunIndexJson) {