type: object
description: |
    Body for creating an email/password account (`POST /auth/account`)
    or attaching email/password to an existing account
    (`POST /auth/account/attach`).
required: [email, password]
properties:
    email: { type: string, format: email }
    password: { type: string, format: password }
    username:
        type: string
        description: Optional username. Server generates one when omitted.
    marketingOptIn:
        type: boolean
        description: Whether the account opts into marketing emails on creation.
example:
    email: "alice@example.com"
    password: "correct horse battery staple"
    username: "alice"
    marketingOptIn: true
