Add example of LLM recall prompt to variables lesson - #2006

Changed pages include:

• index.html - view
• 404.html - view
• checkpoint/index.html - view
• guides/index.html - view
• how-this-works/index.html - view
• itd/index.html - view
• itp/index.html - view
• launch/index.html - view
• overview/index.html - view
• sdc/index.html - view

There are more changes not included in the list