Handle "Connection already exists" error when initializing SQLite database
on Capacitor platforms. The native connection can persist across app
restarts while the JavaScript connection Map is empty, causing a mismatch.
When createConnection fails with "already exists":
- Check if connection exists in JavaScript Map and retrieve it if present
- If not in Map, close the native connection and recreate to sync both sides
- Handle "already open" errors gracefully when opening existing connections
This fixes the issue where clicking "Backup Identifier Seed" would redirect
to StartView instead of SeedBackupView due to database initialization
failures in the router navigation guard.
Fixes navigation issue on both iOS and Android platforms.