Exchange Currency

Recreate the "Exchange Currency" screen in React Native using LumioUI.

Goal: Convert between currencies on a big keypad while a draining ring shows how long the quoted rate holds. Exchanging locks the rate and turns the keypad into a receipt. 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/finance-exchange-currency
```

Or pull just the components: `npx @lumioui/cli add pro/amount-keypad animated-number pro/country-picker icon text`

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

### `amount-keypad` — Money keypad where each key glows under your finger and keys it can’t accept flicker once. Pairs with an amount display that lights up each new digit. Types decimals or fills cents from the right.
- `<AmountKeypad>` ×1

### `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 — Re-prices tick the figure to the new quote instead of jumping.

### `country-picker` — Searchable country list with flags and dial codes that opens from a field or settings row, or sits inline. Picking a country flies its flag into the field. Use the built-in list or bring your own.
- `<CountryFlag>` ×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>` ×4

### `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>` ×16

## 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/finance/exchange-currency.tsx` exporting ExchangeCurrencyScreen. 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/finance-exchange-currency
```

The source lands at `screens/finance/exchange-currency.tsx`.

Screen: https://lumioui.com/screens/finance-exchange-currency