Redesign the network configuration and startup

In our 2020-2022 roadmap, we've added 1 big thing among this one, #18086, and #14567.

Building up on our reflections on the Greeter, the Tor progress bar (#7437 (closed)), the persistent Tor configuration (#5462), the time synchronization (#5774 (closed)), the whole process of deciding how to connect to the network and based on that getting a working Tor should be redesigned as a whole.

While working on this we should be careful about the different aspects mentioned above, their technical feasibility, and how we could propose an incremental process.

Blueprint: https://tails.boum.org/blueprint/network_connection

Related issues

• Blocks #15859: Remove Unsafe Browser