chore: update project structure with contracts and services for CaddyManager, including configuration and Docker integration

CaddyManager.Services/Configurations/ConfigurationsService.cs

@@ -0,0 +1,26 @@
+using NetCore.AutoRegisterDi;
+using Microsoft.Extensions.Configuration;
+using CaddyManager.Contracts.Configurations.Caddy;
+using CaddyManager.Contracts.Configurations.Docker;
+using CaddyManager.Contracts.Configurations;
+
+namespace CaddyManager.Services.Configurations;
+
+/// <inheritdoc />
+[RegisterAsSingleton]
+public class ConfigurationsService(IConfiguration configuration) : IConfigurationsService
+{
+    /// <inheritdoc />
+    public T Get<T>() where T : class
+    {
+        var section = typeof(T).Name;
+        
+        // Have the configuration section name be the section name without the "Configurations" suffix
+        if (section.EndsWith("Configurations"))
+            section = section[..^"Configurations".Length];
+        else if (section.EndsWith("Configuration"))
+            section = section[..^"Configuration".Length];
+        
+        return configuration.GetSection(section).Get<T>() ?? Activator.CreateInstance<T>();
+    }
+}