docs: make code blocks collapsible (#7606)

* added collapsible code feature

* fixed side shadow

* fix build errors

* change design

* make code blocks collapsible

www/apps/book/app/advanced-development/workflows/parallel-steps/page.mdx

@@ -19,7 +19,7 @@ export const highlights = [
   ["23", "parallelize", "Run the steps passed as parameters in parallel."],
 ]
 
-```ts highlights={highlights}
+```ts highlights={highlights} collapsibleLines="1-12" expandButtonLabel="Show Imports"
 import {
   createWorkflow,
   parallelize,