Placing logout button in menu-less application
This particular application does not have a side menu, bottom navigation or a Profile/Account page. Although it requires the user to Sign In to proceed.
NOTE: This is a front-facing application where the user can login to view details and actions from his/her account. That is the reason why it doesn't have any other account-related actions
Usually, the logout/sign out option goes in the side navigation pane or in the account page.
One possible option here is to place the Logout option inside an Ellipses dropdown on the right-top corner of the title bar