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

CaddyManager.Contracts/Models/Caddy/CaddySaveConfigurationRequest.cs

@@ -0,0 +1,22 @@
+namespace CaddyManager.Contracts.Models.Caddy;
+
+/// <summary>
+/// Wraps the information needed to save a Caddy configuration
+/// </summary>
+public class CaddySaveConfigurationRequest
+{
+    /// <summary>
+    /// Indicates if the configuration is new
+    /// </summary>
+    public bool IsNew { get; set; }
+    
+    /// <summary>
+    /// Name of the Caddy configuration file
+    /// </summary>
+    public required string FileName { get; init; } = string.Empty;
+    
+    /// <summary>
+    /// Content of the Caddy configuration file
+    /// </summary>
+    public string Content { get; set; } = string.Empty;
+}