Add foundation

Toolkit.Foundation/ConfigurationInitializer.cs

@@ -0,0 +1,25 @@
+namespace Toolkit.Foundation;
+
+public class ConfigurationInitializer<TConfiguration>(IPublisher publisher,
+    IConfigurationReader<TConfiguration> reader, 
+    IConfigurationWriter<TConfiguration> writer,
+    IConfigurationFactory<TConfiguration> factory) :
+    IConfigurationInitializer<TConfiguration>,
+    IInitializer
+    where TConfiguration :
+    class
+{
+    public async Task Initialize()
+    {
+        if (!reader.TryRead(out TConfiguration? configuration))
+        {
+            if (factory.Create() is object defaultConfiguration)
+            {
+                configuration = (TConfiguration?)defaultConfiguration;
+                writer.Write(defaultConfiguration);
+            }
+        }
+
+        await publisher.PublishUI(new Changed<TConfiguration>(configuration));
+    }
+}