Show the other computers, and apply the ten-minute rule

Three pieces on top of the link:

**The network status window**, on the entry window's Window menu. A row
per station, this computer included the way N1MM shows it: number,
address, operator, band, mode, run, transmit, pass frequency, the last
message type, how long ago it arrived, the counts each way and the echo
round trip. A station that broadcast the wrong version is named under the
table in red — that is the one fault where everything looks connected
and nothing arrives. The box at the bottom sends a line of chat, and
Echo asks every station whether it is there.

**Where this station is** goes out once a second when it has changed.
The frequency, the mode and run have a dozen places they can change from
— the radio moving, a band button, a QSY typed into the callsign box —
so it is read and compared rather than announced from each of them.

**The ten-minute rule.** `BandChangeRules` already counted changes and
the stay on a band, and the entry window already showed the countdown,
but only a user-defined contest carried a rule, so every built-in
contest allowed anything. `ForCategory` gives a multi-operator entry
with one or two transmitters a ten-minute stay, which is N1MM's fallback
in `ContestInstance.BandChangeTimerDuration` for every contest that does
not name its own. Its per-contest table is a few hundred cases in a
decompiled hash switch and is not repeated.

Config ▸ Edit Networked-Computer Names now covers both networks: the
12060 broadcast to other programs and the 12070 link, with the station
number, the port, the version to claim and stations named by address for
a network where a broadcast does not reach.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PdAYHcdRktqKry7nk414TU

src/Nonemm.Contests/BandChangeRules.cs

@@ -22,6 +22,48 @@ public sealed record BandChangeRules(
     /// A contest that does not limit band changes at all.
     public static readonly BandChangeRules None = new(0);
 
+    /// How long a multi-operator entry with one transmitter has to stay on a
+    /// band. It is the ten-minute rule, and it is N1MM's fallback for every
+    /// contest that does not name a number of its own.
+    public static readonly TimeSpan MultiOneStay = TimeSpan.FromMinutes(10);
+
+    /// What a contest allows an entry in this category, before the contest has
+    /// its say. These are N1MM's defaults, from
+    /// `ContestInstance.BandChangeTimerDuration` and `BandChangeCountMax`:
+    ///
+    /// | Category | Changes counted | Stay |
+    /// |---|---|---|
+    /// | single operator | no | none |
+    /// | multi-operator, one transmitter | no | ten minutes |
+    /// | multi-operator, two transmitters | no | ten minutes |
+    /// | multi-operator, more | no | none |
+    ///
+    /// The count is off by default because N1MM's own fallback for it is zero:
+    /// the contests that cap band changes per hour name the cap themselves, and
+    /// a contest class that does so overrides `Contest.BandChangesFor`. The
+    /// stay is the other way round — ten minutes is the fallback, and a contest
+    /// with no rule of its own gets it.
+    ///
+    /// A station with a transmitter per band changes band by moving to another
+    /// radio, so nothing is counted for it.
+    public static BandChangeRules ForCategory(ContestEntry entry)
+    {
+        if (!entry.OperatorCategory.StartsWith("MULTI", StringComparison.OrdinalIgnoreCase))
+        {
+            return None;
+        }
+        // N1MM reads the number of transmitters off the operator category on
+        // Cabrillo 2.0 and off the transmitter category after it. Both are
+        // checked, so an entry written either way is read
+        bool one = Is(entry, "MULTI-ONE", "ONE");
+        bool two = Is(entry, "MULTI-TWO", "TWO");
+        return one || two ? None with { MinimumStay = MultiOneStay } : None;
+    }
+
+    private static bool Is(ContestEntry entry, string operatorCategory, string transmitterCategory) =>
+        entry.OperatorCategory.Equals(operatorCategory, StringComparison.OrdinalIgnoreCase)
+        || entry.TransmitterCategory.Equals(transmitterCategory, StringComparison.OrdinalIgnoreCase);
+
     public bool IsCounted => Max > 0;
 
     /// True for a contest that says how long a station has to stay on a band.