If user followed onboarding flow to recover his account using seed phrase or keycard,
then `ProcessBackedupMessages` property of node config json object should be set to
`true`, otherwise it should be set to `false` or be omitted.
Also, make AccountManager a dependency of Messenger.
This is needed for community token permissions as we'll need a way to access wallet accounts
and sign messages when sending requests to join a community.
The APIs have been mostly taken from GethStatusBackend and personal service.