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.Tests/SmokeTests.cs

@@ -0,0 +1,13 @@
+namespace YKanBan.Tests;
+
+[TestClass]
+public class SmokeTests
+{
+    [TestMethod]
+    public void ThirdPartyPackagesResolve()
+    {
+        Assert.IsNotNull(typeof(Pidgin.Parser).Assembly);
+        Assert.IsNotNull(typeof(Newtonsoft.Json.JsonConvert).Assembly);
+        Assert.IsNotNull(typeof(Microsoft.Data.Sqlite.SqliteConnection).Assembly);
+    }
+}