chore: commit missing files

PcgsInv/App.axaml

@@ -0,0 +1,15 @@
+<Application xmlns="https://github.com/avaloniaui"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+             x:Class="PcgsInv.App"
+             xmlns:local="using:PcgsInv"
+             RequestedThemeVariant="Light">
+
+    <Application.DataTemplates>
+        <local:ViewLocator />
+    </Application.DataTemplates>
+
+    <Application.Styles>
+        <FluentTheme/>
+        <StyleInclude Source="avares://Avalonia.Controls.DataGrid/Themes/Fluent.xaml"/>
+    </Application.Styles>
+</Application>