Closes#5846
Will be moved down to the IPC service eventually.
The goal for connection roaming is not for totally transparent "Change
Wi-Fi networks without dropping SSH" handoffs, but just for Firezone to
re-connect itself as quickly as possible so that everything above us can
re-connect as quickly as it times out, and won't be hung up with a
broken tunnel.
Right now it only works on my dev VM, not on my test VMs, due to #4053
and #4103, but it passes tests and should be safe to merge.
There's one doc fix and one script fix which are unrelated and could be
their own PRs, but they'd be tiny, so I left them in here.
Ref #4106 and #3713 for the plan to fix all this by splitting the tunnel
process off so that the GUI runs as a normal user.
This may cause conflicts with all my other PRs but it has to happen.
```[tasklist]
- [ ] Update test names in branch protection (I don't think I have perms for this)
```
