feat: onboarding flow (6 screens) + audio engine + design system

Onboarding:
- 6-screen flow: Problem → Empathy → Solution → Wow → Personalization → Paywall
- useOnboarding hook with Zustand + AsyncStorage persistence
- MiniTimerDemo with live 20s timer + haptics
- Auto-redirect for first-time users
- Mock RevenueCat for dev testing

Audio:
- useAudioEngine hook with expo-av
- Phase sounds (count_3/2/1, beep, bell, fanfare)
- Placeholder music tracks

Design System:
- Typography component + constants
- GlassView component
- Spacing, shadows, animations, borderRadius constants
- Extended color palette (phase gradients, glass, surfaces)

Timer:
- Fix: handle 0-duration phases (immediate advance)
- Enhanced TimerDisplay with phase gradients

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/shared/constants/animations.ts

@@ -0,0 +1,51 @@
+import { Easing } from 'react-native'
+
+export const DURATION = {
+  SNAP: 60,
+  QUICK: 120,
+  FAST: 300,
+  NORMAL: 400,
+  SLOW: 600,
+  XSLOW: 1000,
+  BREATH: 1800,
+} as const
+
+export const EASING = {
+  STANDARD: Easing.inOut(Easing.ease),
+  DECELERATE: Easing.out(Easing.ease),
+  LINEAR: Easing.linear,
+} as const
+
+export const SPRING = {
+  BOUNCY: { tension: 50, friction: 7 },
+} as const
+
+export const ANIMATION = {
+  PULSE_UP: {
+    toValue: 1.08,
+    duration: DURATION.SNAP,
+    useNativeDriver: true,
+  },
+  PULSE_DOWN: {
+    toValue: 1,
+    duration: DURATION.QUICK,
+    easing: EASING.DECELERATE,
+    useNativeDriver: true,
+  },
+  GRADIENT_CROSSFADE: {
+    toValue: 1,
+    duration: DURATION.SLOW,
+    easing: EASING.STANDARD,
+    useNativeDriver: true,
+  },
+  FADE_IN: {
+    toValue: 1,
+    duration: DURATION.NORMAL,
+    useNativeDriver: true,
+  },
+  BREATH_HALF: {
+    duration: DURATION.BREATH,
+    easing: EASING.STANDARD,
+    useNativeDriver: false,
+  },
+} as const

src/shared/constants/borderRadius.ts

@@ -0,0 +1,11 @@
+export const RADIUS = {
+  XS: 4,
+  SM: 6,
+  MD: 12,
+  LG: 16,
+  XL: 20,
+  '2XL': 28,
+  '3XL': 32,
+  '4XL': 36,
+  FULL: 9999,
+} as const

src/shared/constants/colors.ts

@@ -5,3 +5,72 @@ export const PHASE_COLORS = {
   REST: '#3B82F6',
   COMPLETE: '#22C55E',
 } as const
+
+export const PHASE_GRADIENTS = {
+  IDLE: ['#0A0A14', '#12101F', '#1E1E2E'] as const,
+  GET_READY: ['#451A03', '#92400E', '#D97706'] as const,
+  WORK: ['#450A0A', '#991B1B', '#EA580C'] as const,
+  REST: ['#0C1929', '#1E3A5F', '#2563EB'] as const,
+  COMPLETE: ['#052E16', '#166534', '#16A34A'] as const,
+} as const
+
+export const ACCENT = {
+  ORANGE: '#F97316',
+  ORANGE_GLOW: '#FB923C',
+  RED_HOT: '#EF4444',
+  GOLD: '#FBBF24',
+  WHITE: '#FFFFFF',
+  WHITE_DIM: 'rgba(255, 255, 255, 0.6)',
+  WHITE_FAINT: 'rgba(255, 255, 255, 0.15)',
+} as const
+
+export const BRAND = {
+  PRIMARY: '#F97316',
+  PRIMARY_LIGHT: '#FB923C',
+  SECONDARY: '#FBBF24',
+  DANGER: '#EF4444',
+  SUCCESS: '#22C55E',
+  INFO: '#3B82F6',
+} as const
+
+export const SURFACE = {
+  BASE: '#0A0A14',
+  RAISED: '#12101F',
+  ELEVATED: '#1E1E2E',
+  OVERLAY_LIGHT: 'rgba(255, 255, 255, 0.08)',
+  OVERLAY_MEDIUM: 'rgba(255, 255, 255, 0.15)',
+  OVERLAY_STRONG: 'rgba(255, 255, 255, 0.25)',
+  SCRIM: 'rgba(0, 0, 0, 0.3)',
+} as const
+
+export const TEXT = {
+  PRIMARY: '#FFFFFF',
+  SECONDARY: 'rgba(255, 255, 255, 0.85)',
+  TERTIARY: 'rgba(255, 255, 255, 0.75)',
+  MUTED: 'rgba(255, 255, 255, 0.6)',
+  HINT: 'rgba(255, 255, 255, 0.45)',
+  DISABLED: 'rgba(255, 255, 255, 0.15)',
+} as const
+
+export const BORDER = {
+  SUBTLE: 'rgba(255, 255, 255, 0.05)',
+  LIGHT: 'rgba(255, 255, 255, 0.06)',
+  MEDIUM: 'rgba(255, 255, 255, 0.15)',
+  STRONG: 'rgba(255, 255, 255, 0.3)',
+} as const
+
+export const APP_GRADIENTS = {
+  HOME: ['#0A0A14', '#1A0E2E', '#2D1810'] as const,
+} as const
+
+export const GLASS = {
+  FILL: 'rgba(255, 255, 255, 0.03)',
+  FILL_MEDIUM: 'rgba(255, 255, 255, 0.06)',
+  FILL_STRONG: 'rgba(255, 255, 255, 0.10)',
+  BORDER: 'rgba(255, 255, 255, 0.08)',
+  BORDER_TOP: 'rgba(255, 255, 255, 0.15)',
+  BLUR_LIGHT: 15,
+  BLUR_MEDIUM: 25,
+  BLUR_HEAVY: 40,
+  BLUR_ATMOSPHERE: 60,
+} as const

src/shared/constants/index.ts

@@ -0,0 +1,16 @@
+export {
+  PHASE_COLORS,
+  PHASE_GRADIENTS,
+  ACCENT,
+  BRAND,
+  SURFACE,
+  TEXT,
+  BORDER,
+  APP_GRADIENTS,
+  GLASS,
+} from './colors'
+export { TYPOGRAPHY } from './typography'
+export { SPACING, LAYOUT } from './spacing'
+export { SHADOW, TEXT_SHADOW } from './shadows'
+export { RADIUS } from './borderRadius'
+export { DURATION, EASING, SPRING, ANIMATION } from './animations'

src/shared/constants/shadows.ts

@@ -0,0 +1,44 @@
+import type { TextStyle, ViewStyle } from 'react-native'
+
+export const SHADOW = {
+  BRAND_GLOW: {
+    shadowColor: '#F97316',
+    shadowOffset: { width: 0, height: 4 },
+    shadowOpacity: 0.5,
+    shadowRadius: 20,
+    elevation: 12,
+  } as ViewStyle,
+
+  WHITE_GLOW: {
+    shadowColor: '#FFFFFF',
+    shadowOffset: { width: 0, height: 0 },
+    shadowOpacity: 0.8,
+    shadowRadius: 6,
+  } as ViewStyle,
+} as const
+
+export const TEXT_SHADOW = {
+  BRAND: {
+    textShadowColor: 'rgba(249, 115, 22, 0.5)',
+    textShadowOffset: { width: 0, height: 0 },
+    textShadowRadius: 30,
+  } as TextStyle,
+
+  WHITE_SOFT: {
+    textShadowColor: 'rgba(255, 255, 255, 0.25)',
+    textShadowOffset: { width: 0, height: 0 },
+    textShadowRadius: 30,
+  } as TextStyle,
+
+  WHITE_MEDIUM: {
+    textShadowColor: 'rgba(255, 255, 255, 0.3)',
+    textShadowOffset: { width: 0, height: 0 },
+    textShadowRadius: 20,
+  } as TextStyle,
+
+  DANGER: {
+    textShadowColor: 'rgba(239, 68, 68, 0.6)',
+    textShadowOffset: { width: 0, height: 0 },
+    textShadowRadius: 40,
+  } as TextStyle,
+} as const

src/shared/constants/spacing.ts

@@ -0,0 +1,25 @@
+export const SPACING = {
+  0: 0,
+  0.5: 2,
+  1: 4,
+  1.5: 6,
+  2: 8,
+  2.5: 10,
+  3: 12,
+  3.5: 14,
+  4: 16,
+  5: 20,
+  6: 24,
+  8: 32,
+  10: 40,
+  12: 48,
+  14: 56,
+  15: 60,
+} as const
+
+export const LAYOUT = {
+  PAGE_HORIZONTAL: 24,
+  SECTION_GAP: 40,
+  INLINE_GAP: 16,
+  CONTROLS_GAP: 32,
+} as const

src/shared/constants/typography.ts

@@ -0,0 +1,73 @@
+import type { TextStyle } from 'react-native'
+
+export const TYPOGRAPHY = {
+  countdown: {
+    fontSize: 140,
+    fontWeight: '900',
+    fontVariant: ['tabular-nums'],
+  } as TextStyle,
+
+  timeDisplay: {
+    fontSize: 72,
+    fontWeight: '900',
+    fontVariant: ['tabular-nums'],
+  } as TextStyle,
+
+  brandTitle: {
+    fontSize: 56,
+    fontWeight: '900',
+    letterSpacing: 12,
+  } as TextStyle,
+
+  displayLarge: {
+    fontSize: 42,
+    fontWeight: '900',
+    letterSpacing: 4,
+  } as TextStyle,
+
+  displaySmall: {
+    fontSize: 32,
+    fontWeight: '900',
+    letterSpacing: 20,
+  } as TextStyle,
+
+  buttonHero: {
+    fontSize: 30,
+    fontWeight: '900',
+    letterSpacing: 5,
+  } as TextStyle,
+
+  heading: {
+    fontSize: 24,
+    fontWeight: '800',
+  } as TextStyle,
+
+  buttonMedium: {
+    fontSize: 20,
+    fontWeight: '700',
+    letterSpacing: 2,
+  } as TextStyle,
+
+  body: {
+    fontSize: 18,
+    fontWeight: '700',
+  } as TextStyle,
+
+  caption: {
+    fontSize: 16,
+    fontWeight: '500',
+  } as TextStyle,
+
+  label: {
+    fontSize: 15,
+    fontWeight: '800',
+    letterSpacing: 1,
+  } as TextStyle,
+
+  overline: {
+    fontSize: 11,
+    fontWeight: '600',
+    textTransform: 'uppercase',
+    letterSpacing: 1,
+  } as TextStyle,
+} as const