Say how many QTCs are left with the station being worked

WAE gives a point for every QTC line, so an operator needs to know what is
still there to exchange. The entry window now carries N1MM's QTCinfo line in
WAE: how many QTC lines have already gone with the station in the callsign
box, how many more may go, and how many contacts are left to report to
anybody. The QTC window shows the same line.

The numbers come from the log rows, the way N1MM works them out:

- exchanged is every QTC row with that call, both directions and all bands,
  and ten is the lot
- available is every contact not reported to anybody yet, without the dupes
  and without the station itself, which is N1MM's QTCRecordsetCount
- what is left with the station is what is free of its ten, and no more than
  the contacts there are to report when we are the one reporting

Europe on CW and SSB only takes traffic down, so its line leaves the last
number out, as N1MM's does.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0157i7PiZyqBkquxS9A6FTdQ

src/Nonemm.App/Windows/EntryWindow.axaml

@@ -211,6 +211,11 @@
       <TextBlock Name="PathText" FontSize="11" Opacity="0.75" Margin="2,8,0,0" Text=""
                  TextTrimming="CharacterEllipsis" />
 
+      <!-- WAE only: N1MM's QTCinfo label, which says how much traffic may
+           still be exchanged with the station being worked -->
+      <TextBlock Name="QtcInfoText" FontSize="11" Margin="2,2,0,0" Text="" IsVisible="False"
+                 Foreground="#2980B9" TextTrimming="CharacterEllipsis" />
+
       <TextBlock Name="UserTextText" FontSize="11" Margin="2,2,0,0" Text=""
                  Foreground="#2980B9" TextTrimming="CharacterEllipsis" />