fix: resolve TS build errors and implement mobile auth token storage

[mramansayyad]

Summary

This PR fixes all TypeScript compilation errors inside the @devcard/backend and @devcard/mobile workspace projects, and completes the TODO placeholders in AuthContext.tsx to persist authentication tokens in React Native using AsyncStorage.

Closes #198

Changes Made

1. Backend (apps/backend)

• connect.ts: Direct import/call of encrypt from ../utils/encryption.js and randomBytes from node crypto.
• analytics.ts & connect.ts: Declared route query/parameter types directly on fastify route methods (e.g., app.get<{ Querystring: ... }>) for cleaner type inference.
• auth.ts & connect.ts: Pino error logs updated to app.log.error({ err }, '...') for proper type resolution.
• profiles.test.ts: Cast mockPrisma as any in test decorator.

2. Mobile (apps/mobile)

• AuthContext.tsx: Completed the token load/save/clear flow using @react-native-async-storage/async-storage.
• MainTabs.tsx: Updated imports of ConnectPlatformsScreen and ViewsScreen to named imports.
• SettingsScreen.tsx: Added useNavigation hook.
• Skeleton.tsx: Adjusted prop types to use DimensionValue from React Native.

Verification

• Both backend and mobile compile without errors via tsc.
• All backend unit tests run and pass (44 passed in Vitest).

[Harxhit]

@mramansayyad I am closing this PR as the issue is not assigned to you please wait for issue to get assigned.