Share tab loses state on tab switch (slow workaround in place)

[darthnithin]

Problem

When switching from Request tab back to Share tab, the component loses all state:

• GET link status shows as unlinked
• Donation status (isActive) resets to false
• Shows 'Start Sharing' card instead of Impact card
• Account balances disappear

Root Cause

The Share tab component appears to be remounting when switching tabs, despite using NativeTabs which should keep components mounted. This may be a bug in:

• NativeTabs implementation in SDK 54
• Nested route groups (share) and (request)
• Expo Router tab handling

Current Workaround

Added useFocusEffect hook that reloads all data when tab comes into focus:

• GET link status (getGetLinkStatus)
• GET account balances (getGetAccounts)
• Donation impact data (getDonorImpact)

File: apps/mobile/app/(tabs)/(share)/index.tsx

Why It's Slow

Makes 3 API calls every time you switch tabs:

1. getGetLinkStatus(userId)
2. getGetAccounts(userId)
3. getDonorImpact(userId)

This is noticeable lag when switching tabs.

Ideal Solutions

Option 1: Fix Root Cause

Investigate why component is remounting and prevent it:

• Check NativeTabs behavior in SDK 54
• Test if upgrading to SDK 55 stable (when released) fixes it
• Try different tab layout configurations

Option 2: Cache State in Context

Move GET/donation state to a context provider (similar to TabCacheProvider) so it persists across remounts:

• Create DonorStateProvider
• Store isGetLinked, isActive, monthlyAmount, etc.
• Only make API calls on initial load and explicit refresh

Option 3: Throttle Refresh

Only refresh data if >30 seconds since last refresh, not on every tab switch.

Acceptance Criteria

• Tab switching is instant (no API calls or <100ms)
• State persists correctly across tab switches
• Fresh data still loads on initial mount and pull-to-refresh

References

• NativeTabs docs: https://docs.expo.dev/router/advanced/native-tabs/
• SDK 54 may have remounting issues with nested route groups
• Consider upgrading to SDK 55 stable when released