Implements dataloading

PkmnLib.Tests/Dataloader/ItemDataLoaderTests.cs

@@ -0,0 +1,14 @@
+using PkmnLib.Dataloader;
+
+namespace PkmnLib.Tests.Dataloader;
+
+public class ItemDataLoaderTests
+{
+    [Test]
+    public void TestPrimaryItemFile()
+    {
+        using var stream = File.OpenRead("Data/Items.json");
+        var library = ItemDataLoader.LoadItems(stream);
+        Assert.That(library, Is.Not.Null);
+    }
+}