The information you have provided does not seem concerning at all, though the stuff about a jailbreak might deserve a new question of its own, with more details.
The user name is leandritus and the next field indicates where the user logged in from. Based on your user name here, I assume that’s your original user account.
I guess what happened here is that you lost the password for leandritus and the service guys created a new account macbookpro with a new password for you. There’s a third account mac which has logged in once.
If you have not enabled remote logins over the network recently, I think we can safely assume all of these were made by someone with physical access to the laptop. The ones on tty* are when you log in from a terminal window and the console ones are when you logged in from the login screen.
Again, all of this looks perfectly normal, at least in the absence of additional information to suggest that you have unauthorized activity on your computer.
Also, look at the dates – there were weeks between these crashes.
In some more detail, the last output indicates the user name, the location where the user logged in from (where known), the time of the login, and the duration of the session. See the manual page for details and additional options.
(The man page link is to an online version which might differ slightly from what you have installed. The command man last in a terminal window will display the manual page from your local system, which should be authoritative.)
If you really suspect that something is wrong, reinstalling the operating system using macOS Recovery (or if you have a really old machine, proper installer media such as an official Apple DVD) should always be sufficient to completely reset everything to factory state.
Obviously, you’ll need to make sure you have backups of all your personal files before you do anything drastic, and restore them after the reinstall; but take care to separate out any untrusted executables you might have executed in the past and never run them again if you don’t trust them.