Integrate Canary Check during DB start

[CMCDragonkai]

Specification

The canary check was done in EFS here: MatrixAI/js-encryptedfs#57. This is something we can do in js-db directly so all DB users can benefit.

Tasks

1. Adapt EFS logic to js-db
2. Update tests for js-db
3. Remove the canary check from EFS