* Private Key Stored in Plaintext(SharedPreference) in EncryptionService migrated to EncryptedSharedPreferences.
* Fix: Safe migration to EncryptedSharedPreferences and restore testability
- Use distinct filename for encrypted prefs to avoid collision with legacy plaintext file
- Move Keystore setup to initialize() to support Robolectric test mocks
- Implement safe read-old/write-new migration logic
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Co-authored-by: callebtc <93376500+callebtc@users.noreply.github.com>
