Initial commit: BARON SSO 샘플 (WebView OIDC PKCE 인증 라이브러리 + 데모 앱)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

BaronSoftware.SSO/Features/LoginWindow/LoginWindow.xaml

@@ -0,0 +1,11 @@
+<Window x:Class="BaronSoftware.SSO.LoginWindow"
+        x:ClassModifier="internal"
+        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:wv2="clr-namespace:Microsoft.Web.WebView2.Wpf;assembly=Microsoft.Web.WebView2.Wpf"
+        Title="BARON 로그인" Height="760" Width="520"
+        WindowStartupLocation="CenterOwner">
+    <Grid>
+        <wv2:WebView2 x:Name="webview" />
+    </Grid>
+</Window>