Shop Assistant

Recreate the "Shop Assistant" screen in React Native using LumioUI.

Goal: Shop by chatting with an AI assistant that thinks, streams its reply word by word, then reveals a top pick and two alternatives. Add items straight from the chat and watch your bag total update. Match the reference implementation's layout, behavior, and motion exactly — this is a production screen, not a mockup.

## Setup

Fastest path — install the screen plus its component deps:

```bash
npx @lumioui/cli add pro/ecommerce-shop-assistant
```

Or pull just the components: `npx @lumioui/cli add pro/add-to-cart-button animated-number icon pro/lightbox pro/quick-replies pro/streaming-text text pro/thinking-indicator`

Native packages:
- react-native-reanimated@*
- react-native-safe-area-context@*
- react-native-svg@*

Stack assumptions: Expo SDK 54 / RN 0.81, Reanimated 4, NativeWind v4, TypeScript strict, Expo Go compatible.

## Components — how, where, when

### `add-to-cart-button` — Add button that becomes its own result: busy dots while adding, a check and “In bag”, then a quantity stepper with a trash icon at one. A compact version stretches open over product photos.
- `<AddToCartButton>` ×2

### `animated-number` — Number that moves to each new value as a calm count-up or a roll where only the changed digits turn, set in type or in dot-matrix LEDs whose dots switch on in place. Screen readers announce just the final value, not every step.
- `<AnimatedNumber>` ×1

### `icon` — Icon set drawn on one consistent grid, sized and coloured from your theme. The heart, star and bookmark can fill in place inside their outline, then fade back out.
- `<Icon>` ×7

### `lightbox` — Photo gallery where any tapped photo grows out of its exact tile into a full-screen viewer, then flies back into the tile of whichever photo is showing when you let it go.
- `<LightboxImage>` ×2
- `<LightboxProvider>` ×1

### `quick-replies` — Suggested reply chips that sit above a message composer. Tapping one lights it and can fly it into the conversation as your message, while the other suggestions fade away.
- `<QuickReplies>` ×1

### `streaming-text` — AI reply that appears word by word as it streams in, with the newest words softly highlighted. Screen readers hear the full answer once instead of every fragment.
- `<StreamingText>` ×1

### `text` — Themed type scale from caption to display that follows light and dark mode. Includes a pull-quote style with an accent rule and a quieter dimmed tone for secondary text.
- `<Text>` ×14

### `thinking-indicator` — AI working state with a gently pulsing label and steps that check off as they finish, in a fold-out list or a pill. When done it settles into a summary like “Researched for 8s”.
- `<ThinkingIndicator>` ×2

## Conventions (non-negotiable)

- Styling via NativeWind `className` with semantic tokens only: `bg-background`, `text-foreground`, `bg-card`, `text-card-foreground`, `bg-secondary`, `bg-muted`, `text-muted-foreground`, `bg-accent`, `bg-destructive`, `border-border`. Hard-coded colors only inside media overlays (`text-white`, `bg-black/N`).
- Motion via the token presets from `@lumioui/core` (`spring.press`, `spring.surface`, `spring.glide`, `timing.fast`, `timing.slow`, …) — no bespoke spring configs or durations.
- Gate transform motion behind `useReducedMotion()`; keep opacity/color feedback, drop travel and overshoot.
- Haptics via `useHaptic()`: `light` on press, `selection` on toggle/select, `warning` on invalid input. Never import expo-haptics directly.
- Press feedback via `usePressAnimation()` (~0.97 scale), not `activeOpacity` tricks.
- a11y: `accessibilityRole` + `accessibilityLabel` on every control, touch targets ≥44pt.
- Entrance choreography: staggered `Mount` wrappers (delay 0/60/120…) so regions land in sequence instead of popping in at once.
- Wrap the screen in `SafeAreaView`; keep dark mode working via the semantic tokens.

## Deliverable

One file: `screens/ecommerce/shop-assistant.tsx` exporting ShopAssistantScreen. Preserve the props interface — the host app wires the callbacks (navigation, submit handlers) through them.

## Reference implementation

This is a LumioUI Pro item: its source is not published in the docs. Install it with a Pro license key
(set `LUMIO_LICENSE_KEY`; keys are on lumioui.com/account) and read the installed file as the reference:

```bash
npx @lumioui/cli add pro/ecommerce-shop-assistant
```

The source lands at `screens/ecommerce/shop-assistant.tsx`.

Screen: https://lumioui.com/screens/ecommerce-shop-assistant