* feat: add verifier when contract is initialized
* feat: initialize git repository on new mint
* feat: add created at in token entity
* feat: add created at in ap entity
* feat: handle verifier role grant and revoke
* feat: add verified field to token
* refactor: create constants file
* feat: add total tokens counter on collection entity
* refactor: verify verifier address for mint event
* refactor: remove collection id