sendSequenceEmail
Send a manual email step from the signed-in user's Gmail mailbox, then complete the task with
outcome SENT. Refusals carry extensions.code: NO_MAILBOX, NEEDS_REAUTH, CAP_REACHED, a
SequenceEmailBlock value, SEND_FAILED, or SENT_BUT_NOT_RECORDED (the email went; do not resend).
sendSequenceEmail(
input: SendSequenceEmailInput!
): SendSequenceEmailResult!
