Add cache warming and prefetching strategies for critical data

[RUKAYAT-CODER]

Background

On app start, user must wait for critical data (user profile, initial courses). Implement cache warming: fetch critical data during splash screen, prefetch in background. Dramatically reduces time-to-first-paint and improves cold start experience.

Description

Implement cache warming during splash screen to preload critical data before user reaches home screen.

Current Behavior

User sees blank/loading screen while critical data fetches

Expected Behavior

Critical data fetched during splash screen. Home screen ready instantly.

Impact

⚡ Home screen loads 50%+ faster
✨ No loading spinners on first navigation
🎯 Better first impression

Acceptance Criteria

• Identify critical data for cold start (user profile, initial courses)
• Implement cache warming in splash screen
• Fetch critical data before SplashScreen.hideAsync()
• Cold start time to home screen reduced by 50%+
• No loading spinners on first screen
• Test on slow 3G network
• Document cache warming strategy
• Monitor cold start metrics

Implementation Hints

In App.tsx prepareApp, add cache warming fetches. Use Promise.all for parallel loads. Fallback to empty state if fetch fails.

Performance Metrics

Before:

• homeScreenLoadTime: 3-5s after tap

After (Target):

• homeScreenLoadTime: 1-2s (-60%)

Related Issues

• feat created new mobile message ui #19
• feat: add mobile video player component with controls and picture-in-… #20
• Implement Offline Mode and Data Sync #21
• feat/mobile test taking #23