Zoom the text of the log, check, available and bandmap windows

Ctrl+wheel and Ctrl+plus / Ctrl+minus change the text size of the
window in front, and Ctrl+0 puts it back. Each size is kept in the
settings file.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/Nonemm.App/Configuration/Settings.cs

@@ -63,6 +63,14 @@ public sealed record Settings
     /// The height of the callsigns on the bandmap, in points.
     public int BandmapTextSize { get; init; } = 12;
 
+    /// The text size of the log, check and available windows, in points. Ctrl
+    /// with the mouse wheel or plus and minus changes the one in front.
+    public int LogFontSize { get; init; } = 12;
+
+    public int CheckFontSize { get; init; } = 14;
+
+    public int AvailableFontSize { get; init; } = 13;
+
     /// Moves each incoming CW spot by a few tens of hertz, so the operator has
     /// to find the station by ear. N1MM calls it randomising.
     public bool RandomizeSpots { get; init; }