feat: close v1 feature gaps — freemium gating, video/audio infrastructure, EAS build config

- Add access control service with 3 free workouts (IDs 1, 11, 43), paywall gating on workout detail and lock indicators on explore grid
- Wire VideoPlayer into player background and workout detail preview
- Add placeholder HLS video URLs to 5 sample workouts (Apple test streams)
- Add test audio URLs to music service MOCK_TRACKS for all vibes
- Switch RevenueCat API key to env-based with sandbox fallback
- Create eas.json with development/preview/production build profiles
- Update app.json with iOS privacy descriptions (HealthKit, Camera) and non-exempt encryption flag
- Create collection detail screen (route crash fix)
- Replace hardcoded profile stats with real activity store data
- Add unlockWithPremium i18n key in EN/FR/DE/ES

app/player/[id].tsx

@@ -36,6 +36,7 @@ import { useTranslatedWorkout } from '@/src/shared/data/useTranslatedData'
 import { useWatchSync } from '@/src/features/watch'
 
 import { track } from '@/src/shared/services/analytics'
+import { VideoPlayer } from '@/src/shared/components/VideoPlayer'
 import { BRAND, PHASE_COLORS, GRADIENTS, darkColors } from '@/src/shared/theme'
 import type { ThemeColors } from '@/src/shared/theme/types'
 import { TYPOGRAPHY } from '@/src/shared/constants/typography'
@@ -461,9 +462,12 @@ export default function PlayerScreen() {
     <View style={styles.container}>
       <StatusBar hidden />
 
-      {/* Background gradient */}
-      <LinearGradient
-        colors={[colors.bg.base, colors.bg.surface]}
+      {/* Background video or gradient fallback */}
+      <VideoPlayer
+        videoUrl={workout?.videoUrl}
+        gradientColors={[colors.bg.base, colors.bg.surface]}
+        mode="background"
+        isPlaying={timer.isRunning && !timer.isPaused}
         style={StyleSheet.absoluteFill}
       />