Get rid of local linux account for single user account management

I have a working ssh-vault-helper setup. However, in order to get it working, the username has to exist locally in my linux machine. Is there a way to avoid this so that I'll only be managing the username in Vault?

No files, tests, or entry points are identified. Start by reviewing how the SSH helper validates the requested local Linux username and uses Vault, then define the supported account-management behavior; done means a user can manage the username only in Vault without a local account.

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