onion-tunnel: report connection status via scaffolding
- To enable applications to get more of an insight into usage of the
proxy, we now report various events about connection state via the
TunnelScaffolding
mechanism. - Three new events,
on_established
,on_socket_close
, andon_arti_failure
enable the scaffolding to be notified about important state changes per-connection. - We also provide a helper function to get circuit details without
having to depend on the arti
tor-*
crates directly.
Helps with #38 (closed). Nothing uses this yet (that'll come later once I resume work on that ticket), but I might as well push up what I've done so far...