IPv6 addresses are not escaped inside net: addresses

If I do

```
sbot server --host=:: --port=8100 --ws.port=8101&
sbot getAddress -- --host=::1 --port=8100
```
I get:

```
net::::8100~ ... ;ws://[::]:8101
```

Is that desired behaviour because the square brackets are needed because the ws address is actually a URL and the net: address is not? Or is it a bug and it should be `net:[::]:8100`? cc @dominictarr 