refactor(m0): restructure project and install dependencies

- Clean Avalonia template content (ViewLocator, greeting, empty Models folder)
- Add YKanBan.Tests (MSTest 4.4.1) to solution
- Install packages per plan version table (Semi.Avalonia, Lucide icons,
  Microsoft.Data.Sqlite, Pidgin, Newtonsoft.Json 13.0.4 fallback)

YKanBan/YKanBan.csproj

@@ -9,7 +9,6 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <Folder Include="Models\" />
     <AvaloniaResource Include="Assets\**" />
   </ItemGroup>
 
@@ -18,11 +17,16 @@
     <PackageReference Include="Avalonia.Desktop" Version="11.3.6" />
     <PackageReference Include="Avalonia.Themes.Fluent" Version="11.3.6" />
     <PackageReference Include="Avalonia.Fonts.Inter" Version="11.3.6" />
-    <!--Condition below is needed to remove Avalonia.Diagnostics package from build output in Release configuration.-->
+    <!--Exclude Avalonia.Diagnostics from Release build output.-->
     <PackageReference Include="Avalonia.Diagnostics" Version="11.3.6">
       <IncludeAssets Condition="'$(Configuration)' != 'Debug'">None</IncludeAssets>
       <PrivateAssets Condition="'$(Configuration)' != 'Debug'">All</PrivateAssets>
     </PackageReference>
     <PackageReference Include="CommunityToolkit.Mvvm" Version="8.2.1" />
+    <PackageReference Include="Semi.Avalonia" Version="11.2.1.10" />
+    <PackageReference Include="IconPacks.Avalonia.Lucide" Version="2.0.0" />
+    <PackageReference Include="Microsoft.Data.Sqlite" Version="9.0.20" />
+    <PackageReference Include="Pidgin" Version="3.5.1" />
+    <PackageReference Include="Newtonsoft.Json" Version="13.0.4" />
   </ItemGroup>
 </Project>