New user onboarding or tutorial exists

First-time users who land in a blank chat interface with no guidance do not know what your product is better at than ChatGPT, where the power features live, or what phrasing produces the best results. They bounce in under sixty seconds. Onboarding — even a single modal with three slides and four starter prompts — measurably shifts day-one activation and week-one retention on AI products, because the cold-start problem is the dominant source of churn for this category.

Gate a 3-step welcome modal on a localStorage.getItem('onboarding_v1') flag. Step 1 explains the product's differentiator in one sentence; step 2 shows four starter prompts the user can click to begin; step 3 points at regenerate, copy, and history. Set the flag on completion or skip. Implement in src/components/onboarding/welcome-modal.tsx.

{!localStorage.getItem('onboarding_v1') && <OnboardingModal onComplete={() => localStorage.setItem('onboarding_v1', '1')} />}