Refactor DTOs for improved structure and documentation

Transitioned from records to classes for flexibility, added XML documentation for clarity, and updated property definitions to use standard getters and setters. Introduced the `required` keyword for essential properties, removed unnecessary constructors, and enhanced property descriptions for better readability. Additionally, overridden `GetHashCode` in `ReceiverReadDto` for proper collection behavior.

EnvelopeGenerator.Application/DTOs/DocumentReceiverElementDto.cs

@@ -1,26 +1,96 @@
 using DigitalData.Core.Abstractions;
 using Microsoft.AspNetCore.Mvc;
 
-namespace EnvelopeGenerator.Application.DTOs
+namespace EnvelopeGenerator.Application.DTOs;
+
+/// <summary>
+/// Data Transfer Object representing a positioned element assigned to a document receiver.
+/// </summary>
+[ApiExplorerSettings(IgnoreApi = true)]
+public class DocumentReceiverElementDto : IUnique<int>
 {
-    [ApiExplorerSettings(IgnoreApi = true)]
-    public record DocumentReceiverElementDto(
-        int Id,
-        int DocumentId,
-        int ReceiverId,
-        int ElementType,
-        double X,
-        double Y,
-        double Width,
-        double Height,
-        int Page,
-        bool Required,
-        string? Tooltip,
-        bool ReadOnly,
-        int AnnotationIndex,
-        DateTime AddedWhen,
-        DateTime? ChangedWhen,
-        double Top,
-        double Left
-        ): IUnique<int>;
+    /// <summary>
+    /// Gets or sets the unique identifier of the element.
+    /// </summary>
+    public int Id { get; set; }
+
+    /// <summary>
+    /// Gets or sets the identifier of the associated document.
+    /// </summary>
+    public int DocumentId { get; set; }
+
+    /// <summary>
+    /// Gets or sets the identifier of the receiver.
+    /// </summary>
+    public int ReceiverId { get; set; }
+
+    /// <summary>
+    /// Gets or sets the type of the element.
+    /// </summary>
+    public int ElementType { get; set; }
+
+    /// <summary>
+    /// Gets or sets the X coordinate of the element.
+    /// </summary>
+    public double X { get; set; }
+
+    /// <summary>
+    /// Gets or sets the Y coordinate of the element.
+    /// </summary>
+    public double Y { get; set; }
+
+    /// <summary>
+    /// Gets or sets the width of the element.
+    /// </summary>
+    public double Width { get; set; }
+
+    /// <summary>
+    /// Gets or sets the height of the element.
+    /// </summary>
+    public double Height { get; set; }
+
+    /// <summary>
+    /// Gets or sets the page number where the element appears.
+    /// </summary>
+    public int Page { get; set; }
+
+    /// <summary>
+    /// Gets or sets a value indicating whether the element is required.
+    /// </summary>
+    public bool Required { get; set; }
+
+    /// <summary>
+    /// Gets or sets the tooltip text for the element.
+    /// </summary>
+    public string? Tooltip { get; set; }
+
+    /// <summary>
+    /// Gets or sets a value indicating whether the element is read-only.
+    /// </summary>
+    public bool ReadOnly { get; set; }
+
+    /// <summary>
+    /// Gets or sets the annotation index for ordering or reference.
+    /// </summary>
+    public int AnnotationIndex { get; set; }
+
+    /// <summary>
+    /// Gets or sets the timestamp when the element was added.
+    /// </summary>
+    public DateTime AddedWhen { get; set; }
+
+    /// <summary>
+    /// Gets or sets the timestamp when the element was last changed, if applicable.
+    /// </summary>
+    public DateTime? ChangedWhen { get; set; }
+
+    /// <summary>
+    /// Gets or sets the top position of the element (in layout terms).
+    /// </summary>
+    public double Top { get; set; }
+
+    /// <summary>
+    /// Gets or sets the left position of the element (in layout terms).
+    /// </summary>
+    public double Left { get; set; }
 }