Sync engage-native docs with Expo 55 / RN 0.83 upgrade

[mintlify]

Summary

Syncs documentation for d-sports-engage-native after d-sports-ecosystem/d-sports-engage-native@db908c4 merged the full codebase into main.

Files changed in trigger repo

• Full repository initial commit (421 files) including Expo 55, React Native 0.83, TypeScript 5.9, EAS CI workflow, widgets support, and native tab bar implementation.

Doc pages updated

repositories/d-sports-engage-native.mdx

• Updated tech stack table: Expo 54 → 55, React Native 0.81 → 0.83, added TypeScript 5.9, Zustand 5, MMKV 4, Reanimated 4
• Added environment variables table documenting all EXPO_PUBLIC_* keys
• Updated "what changed" section with SDK upgrade, native tab bar, EAS OTA CI, and widgets
• Expanded getting started steps with env setup and TypeScript check

repositories/d-sports-engage-native/architecture.mdx

• Added project directory structure overview
• Documented modular screen architecture pattern (thin render shells + extracted hooks)
• Added Zustand + MMKV state management details
• Documented platform-specific tab bar behavior (iOS NativeTabs vs Android/web PillTabBar)
• Added CI/OTA updates section covering the EAS Update workflow