Add KMP Encryption Support

[teogor]

Description

Currently, stitch uses standard SQLite drivers which do not provide built-in encryption. For many KMP applications, data-at-rest encryption is a critical requirement. This task involves researching and implementing a standardized way to enable encryption across Android, iOS, JVM, and potentially Web.

Technical Analysis

Room 3 KMP relies on the SQLiteDriver interface. To support encryption, we need to:

1. Identify suitable SQLCipher or similar wrappers that satisfy the SQLiteDriver interface for each platform.
2. Provide a unified API in StitchRoomConfig to pass a passphrase or encryption configuration.

Proposed Implementation

1. Encryption DSL:

   stitchRoom(context) {
     encryption {
       passphrase = "secure-key"
       // Optional configuration like cipher type
     }
   }

2. Platform Bridges: Implement factory functions for encrypted drivers.
   • Android: Use SQLCipher via androidx.sqlite.db.SupportSQLiteOpenHelper.
   • iOS: Use a native SQLCipher wrapper.
   • JVM: Use sqlite-jdbc with encryption support.

Goals

• Research library compatibility (e.g., SQLCipher, Kermit-SQLite? etc.) for KMP.
• Implement enableEncryption(passphrase) in StitchRoomConfig.
• Provide platform-specific implementations for encrypted drivers.