feat(deps): Upgrade to Expo 54, React 19, RN 0.81, React Navigation 7

[giolaq]

Closes #71

Summary

Upgrades all core dependencies to their latest versions:

Package	Before	After
Expo	51	54
React	18.2	19.1
React Native (tvOS)	0.74	0.81
React Navigation	6.x	7.x
react-tv-space-navigation	3.6	6.0.0-beta1
TypeScript	5.3	5.7
react-native-reanimated	3.10	3.17
react-native-screens	3.31	4.9
react-native-safe-area-context	4.10	5.4
react-native-gesture-handler	2.16	2.24

Breaking changes addressed

• React Navigation 7: Removed animationEnabled from drawer screen options (no longer a valid prop)
• react-tv-space-navigation v5+: Removed deprecated numberOfRenderedItems and numberOfItemsVisibleOnScreen props from SpatialNavigationVirtualizedList — now auto-calculated based on parent view size
• React 19: Removed react-test-renderer (deprecated), updated @types/react to 19.x

Scope

• ✅ apps/expo-multi-tv — fully upgraded
• ✅ packages/shared-ui — types and TS version updated
• ⏭️ apps/vega — not touched (uses @amazon-devices/* scoped packages with separate versioning)

Notes

• react-tv-space-navigation 6.0.0 stable hasn't been released yet — using 6.0.0-beta1 which is the only version with React 19 compatibility
• 74 pre-existing TS errors remain (all "Cannot find module" for peer deps in shared-ui — not introduced by this PR)

Testing

• Android TV
• Fire TV (Fire OS)
• Fire TV (Vega OS) — N/A, vega app unchanged
• Apple TV (tvOS)
• Web