Say when there is nobody to contact

Two freshly wiped devices joined the same network, each got an address,
and nothing happened. The report said "none known yet; nobody else has
joined", which reads as patience — as if somebody were expected and had
not arrived. What had actually happened is that neither agent had anywhere
to look: this project publishes nothing about who is in which network, so
a first meeting needs one of them to be told the other's endpoint id, and
the hints an agent remembers from earlier sessions had gone with the wipe.

Candidates are now in the report, and having none of them with nobody
connected is said plainly, with both ways out of it and this device's own
id ready to hand to the other side. Having some and no sessions yet is the
ordinary state of a network coming up, and stays ungraded.

The local control protocol is 12.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

README.md

@@ -95,6 +95,13 @@ and join the same network with the secret that was printed:
 ./target/release/tsunagi join --network lab --secret tsn1...
 ```
 
+**`--peer` is how the first meeting happens.** Two agents that have never
+met have nothing to go on: this project publishes nothing about who is in
+which network, by design. One of them has to be told the other's endpoint
+id — after that each remembers the other and finds it again by itself, so
+it is needed once. An agent with nobody to contact says so in `status`
+rather than sitting there looking patient.
+
 Within a few seconds both print something like:
 
 ```text