class SecuVaultError(Exception):
    """Base exception for all SecuVault domain errors."""

class AuthenticationError(SecuVaultError):
    """Bad credentials or inactive account."""

class AccessDeniedError(SecuVaultError):
    """User is not authorised to access the requested resource."""

class SecretNotFoundError(SecuVaultError):
    """Requested secret does not exist."""

class TeamNotFoundError(SecuVaultError):
    """Requested team does not exist."""

class ConflictError(SecuVaultError):
    """Optimistic-locking detected a concurrent modification conflict."""