Initial commit: SWP.Core enterprise framework with multi-tenant architecture, configuration management, security, telemetry and comprehensive test suite

Core/CommandQueries/ProblemDetails.cs

@@ -0,0 +1,56 @@
+namespace SWP.Core.CommandQueries;
+
+/// <summary>
+/// Represents a standardized error response according to RFC 9457 (Problem Details for HTTP APIs).
+/// This class provides a consistent way to communicate errors in HTTP APIs, including details about the error type,
+/// status code, and additional context. It also supports extensions for custom error information.
+/// 
+/// RFC 9457 Documentation: https://www.rfc-editor.org/rfc/rfc9457.html
+/// </summary>
+public class ProblemDetails
+{
+    /// <summary>
+    /// A URI reference that identifies the problem type. This is typically a link to human-readable documentation about the error.
+    /// </summary>
+    public string Type { get; set; }
+
+    /// <summary>
+    /// A short, human-readable summary of the problem. It should not change between occurrences of the same error.
+    /// </summary>
+    public string Title { get; set; }
+
+    /// <summary>
+    /// The HTTP status code generated by the server for this occurrence of the problem. This allows the client to understand the general category of the error.
+    /// </summary>
+    public int? Status { get; set; }
+
+    /// <summary>
+    /// A human-readable explanation specific to this occurrence of the problem. It provides additional details about the error.
+    /// </summary>
+    public string Detail { get; set; }
+
+    /// <summary>
+    /// A URI reference that identifies the specific occurrence of the problem. This can be used to trace the error in logs or debugging tools.
+    /// </summary>
+    public string Instance { get; set; }
+
+    /// <summary>
+    /// A dictionary for additional, custom error information. This allows extending the problem details with application-specific fields.
+    /// </summary>
+    [Newtonsoft.Json.JsonExtensionData]
+    public Dictionary<string, object> Extensions { get; } = new();
+
+    /// <summary>
+    /// Adds a custom extension to the problem details.
+    /// </summary>
+    /// <param name="key">The key for the extension.</param>
+    /// <param name="value">The value of the extension.</param>
+    public void AddExtension(string key, object value) => Extensions.Add(key, value);
+
+
+    /// <summary>
+    /// Removes a custom extension from the problem details.
+    /// </summary>
+    /// <param name="key">The key of the extension to remove.</param>
+    public void RemoveExtension(string key) => Extensions.Remove(key);
+}