Go somewhere when the connect succeeds

It was not spinning and stopping. It was working, and then looking exactly
like it had not: `frq.state` does `(reset! screen :chats)` on 001 and the
phone's connect! did not, so a successful registration put the Connect button
back on the same screen and said "Connected as frq-guest" in the small grey
text beside it. There was nothing to tell it from a failure.

So 001 moves off the connect screen here too, and there is somewhere to
land — the status with its live dot, what the server said, and the way back.
Deliberately small: the desktop goes to :chats, and that screen reads rooms,
messages, avatars and the media plane, which is most of what is not ported.

Two things fixed on the way in and out.

A close we asked for came back as "closed by the server", which is untrue and
alarming; a flag tells a Disconnect from a drop, and only a drop reports.

And an unexpected close now says what the last line was and how many came
before it — a connection that registers and then drops is a different bug
from one that never registers, and only that tells them apart.

Verified on the device: Connect lands on the connected screen with the MOTD,
PING/PONG keeps it up, Disconnect returns to the connect screen with no
banner, and a drop would name itself.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>