When building client without CGO, user.Lookup
attempts to get user from /etc/passwd
Which doesn't have the user as MacOS uses
opendirectoryd as user directory
This PR fixes issues with the terminal when
running netbird ssh to a remote agent.
Every session looks up a user and loads its
profile. If no user is found, the connection is rejected.
The default user is root.
This PR adds support for SSH access through the NetBird network
without managing SSH skeys.
NetBird client app has an embedded SSH server (Linux/Mac only)
and a netbird ssh command.
