Add FAQ: "How do I get started generating images from prompts?"

[cbrownstein-lambda]

Closes: #92

[cloudflare-workers-and-pages[bot]]

Deploying with    Cloudflare Pages

Latest commit:	8ae4ab5
Status:	✅  Deploy successful!
Preview URL:	https://64c3501a.lambda-docs.pages.dev
Branch Preview URL:	https://get-started-prompt-to-image.lambda-docs.pages.dev

View logs

[cbrownstein-lambda]

This PR hasn't been touched since February ⇒ closing.