feat(mobile): init SQLite for offline-first support

[yogesh4216]

issue: #123

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Description

This PR initializes SQLite for the mobile app to support an offline-first architecture.

On first app launch, a local SQLite database (blob.db) is created and initialized.
A reusable database access layer is added so the connection can be safely used across the app without re-initialization.

The setup is intentionally minimal and focused only on initialization, as required by the issue.

Key points:
• Database is created on first launch
• Initialization is safe to call multiple times
• Uses Expo SDK 54–compatible async SQLite API
• Includes a placeholder schema for future expansion

This lays the groundwork for offline data storage without introducing any business logic or sync behavior.

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Dependency changes (if applicable)

Added:
expo-sqlite — for local SQLite support on Expo (SDK 54 compatible)

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Summary

This PR initializes SQLite for the mobile app to support an offline-first architecture.

What was done

• Added expo-sqlite (SDK 54 compatible)
• Implemented a reusable singleton database connection
• Ensured database is created on first app launch (blob.db)
• Added initial schema via migrations
  • Placeholder meta table for future use
• Initialization is safe to call multiple times

Notes

• Uses the new async SQLite API (openDatabaseAsync) required by Expo SDK 54
• No app data or sync logic included (intentionally out of scope)

Checklist

• SQLite initialized on first launch
• Reusable DB connection
• Expo-compatible solution
• No ORM / CRUD / remote sync (per issue scope)

Screenshots

[OpenGitBot]

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[OpenGitBot]

Hey @yogesh4216

Your PR has been merged 🥳🥳 and you have earned 20 points.

Thanks for contributing in OpenCode'25✨✨