Add the Avalonia application and the station network

The entry window types contacts and colours them as they are typed; the log,
check, bandmap, score and packet windows read the same session. Contacts are
shared with the other stations of a multi-operator entry in N1MM's contact
message, so an N1MM station on the same network sees them too.

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

src/Nonemm.App/Windows/EntryWindow.axaml

@@ -0,0 +1,92 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        x:Class="Nonemm.App.Windows.EntryWindow"
+        Title="Nonemm"
+        Width="620" SizeToContent="Height"
+        CanResize="True"
+        FontFamily="Inter, sans-serif">
+  <Window.Styles>
+    <Style Selector="TextBlock.label">
+      <Setter Property="FontSize" Value="11" />
+      <Setter Property="Opacity" Value="0.7" />
+      <Setter Property="Margin" Value="2,0,0,1" />
+    </Style>
+    <Style Selector="TextBox.entry">
+      <Setter Property="FontFamily" Value="monospace" />
+      <Setter Property="FontSize" Value="20" />
+      <Setter Property="Padding" Value="6,2" />
+      <Setter Property="VerticalContentAlignment" Value="Center" />
+    </Style>
+    <Style Selector="Button.fkey">
+      <Setter Property="FontSize" Value="11" />
+      <Setter Property="Padding" Value="6,3" />
+      <Setter Property="Margin" Value="0,0,3,0" />
+    </Style>
+  </Window.Styles>
+
+  <DockPanel>
+    <Menu DockPanel.Dock="Top">
+      <MenuItem Header="_File">
+        <MenuItem Header="_New Database…" Click="OnNewDatabase" />
+        <MenuItem Header="_Open Database…" Click="OnOpenDatabase" />
+        <Separator />
+        <MenuItem Header="New _Contest…" Click="OnNewContest" />
+        <MenuItem Header="Open Con_test…" Click="OnOpenContest" />
+        <Separator />
+        <MenuItem Header="Export _Cabrillo…" Click="OnExportCabrillo" />
+        <MenuItem Header="Export _ADIF…" Click="OnExportAdif" />
+        <MenuItem Header="_Import ADIF…" Click="OnImportAdif" />
+        <Separator />
+        <MenuItem Header="E_xit" Click="OnExit" />
+      </MenuItem>
+      <MenuItem Header="_View">
+        <MenuItem Header="_Log" Click="OnShowLog" />
+        <MenuItem Header="_Check" Click="OnShowCheck" />
+        <MenuItem Header="_Bandmap" Click="OnShowBandmap" />
+        <MenuItem Header="_Score Summary" Click="OnShowScore" />
+        <MenuItem Header="_Packet" Click="OnShowPacket" />
+      </MenuItem>
+      <MenuItem Header="_Config">
+        <MenuItem Header="_Station…" Click="OnStationSettings" />
+        <MenuItem Header="_Radio…" Click="OnRadioSettings" />
+        <MenuItem Header="_Cluster…" Click="OnClusterSettings" />
+        <MenuItem Header="_Network…" Click="OnNetworkSettings" />
+        <Separator />
+        <MenuItem Header="Download Country _File" Click="OnDownloadCountryFile" />
+        <MenuItem Header="Download Check _Partial File" Click="OnDownloadCallDatabase" />
+        <MenuItem Header="Reload Support Files" Click="OnReloadSupportFiles" />
+      </MenuItem>
+    </Menu>
+
+    <Border DockPanel.Dock="Bottom" Padding="6,4" BorderThickness="0,1,0,0"
+            BorderBrush="#33808080">
+      <WrapPanel Name="FunctionKeys" />
+    </Border>
+
+    <StackPanel Margin="6">
+      <Grid ColumnDefinitions="Auto,Auto,Auto,*,Auto" Margin="0,0,0,6">
+        <TextBlock Name="FrequencyText" FontFamily="monospace" FontSize="20" Text="14025.00" />
+        <TextBlock Grid.Column="1" Name="ModeText" FontFamily="monospace" FontSize="20"
+                   Margin="10,0,0,0" Text="CW" />
+        <Border Grid.Column="2" Name="RunBorder" Margin="10,2" Padding="6,1" CornerRadius="3"
+                Background="#22808080">
+          <TextBlock Name="RunText" FontSize="12" Text="S&amp;P" />
+        </Border>
+        <TextBlock Grid.Column="3" Name="ContestText" FontSize="12" Opacity="0.75"
+                   VerticalAlignment="Center" Margin="12,0,12,0" Text="no contest"
+                   TextTrimming="CharacterEllipsis" ClipToBounds="True" />
+        <TextBlock Grid.Column="4" Name="ClockText" FontFamily="monospace" FontSize="20"
+                   Text="00:00:00Z" />
+      </Grid>
+
+      <Grid Name="EntryGrid" ColumnDefinitions="Auto" RowDefinitions="Auto,Auto" />
+
+      <Border Name="VerdictBorder" Margin="0,6,0,0" Padding="6,3" CornerRadius="3"
+              Background="#22808080">
+        <TextBlock Name="VerdictText" FontSize="12" Text="" />
+      </Border>
+
+      <TextBlock Name="StatusText" FontSize="11" Opacity="0.7" Margin="2,4,0,0" Text="" />
+    </StackPanel>
+  </DockPanel>
+</Window>