refactor(DocumentReceiverElement): Trenne .NET- und .NET Framework-spezifische Initialisierung in DocumentReceiverElement

- Verschiebe Standardwerte für Id, Required, ReadOnly und AnnotationIndex in den Konstruktor für .NET Framework
- Passe #if-Direktiven an, um Namensräume und NotMapped-Eigenschaften korrekt zu handhaben
- Entferne redundante Standardwert-Zuweisungen bei Property-Deklarationen
- Bereite Klasse für plattformübergreifende Nutzung vor

EnvelopeGenerator.Domain/Entities/DocumentReceiverElement.cs

@@ -6,15 +6,30 @@ using System;
 #endif
 
 namespace EnvelopeGenerator.Domain.Entities
+#if NET
+    ;
+#elif NETFRAMEWORK
+    {
+#endif
+
+[Table("TBSIG_DOCUMENT_RECEIVER_ELEMENT", Schema = "dbo")]
+public class DocumentReceiverElement
 {
-    [Table("TBSIG_DOCUMENT_RECEIVER_ELEMENT", Schema = "dbo")]
+    public DocumentReceiverElement()
-    public class DocumentReceiverElement
     {
         // TODO: * Check the Form App and remove the default value
+#if NETFRAMEWORK
+        Id = -1;
+        Required = false;
+        ReadOnly = false;
+        AnnotationIndex = 0;
+#endif
+    }
+
     [Key]
     [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
     [Column("GUID")]
-        public int Id { get; set; } = -1;
+    public int Id { get; set; }
 
     [Required]
     [Column("DOCUMENT_ID")]
@@ -54,26 +69,23 @@ namespace EnvelopeGenerator.Domain.Entities
     [DefaultValue(1)]
     public int Page { get; set; }
 
-        // TODO: * Check the Form App and remove the default value
     [Required]
     [Column("REQUIRED")]
     [DefaultValue(false)]
-        public bool Required { get; set; } = false;
+    public bool Required { get; set; }
 
     [Column("TOOLTIP")]
     public string Tooltip { get; set; }
 
-        // TODO: * Check the Form App and remove the default value
     [Required]
     [Column("READ_ONLY")]
     [DefaultValue(false)]
-        public bool ReadOnly { get; set; } = false;
+    public bool ReadOnly { get; set; }
 
-        // TODO: * Check the Form App and remove the default value
     [Required]
     [Column("ANNOTATION_INDEX")]
     [DefaultValue(0)]
-        public int AnnotationIndex { get; set; } = 0;
+    public int AnnotationIndex { get; set; }
 
     [Required]
     [Column("ADDED_WHEN", TypeName = "datetime")]
@@ -89,10 +101,15 @@ namespace EnvelopeGenerator.Domain.Entities
     [ForeignKey("ReceiverId")]
     public virtual Receiver Receiver { get; set; }
 
+#if NETFRAMEWORK
     [NotMapped]
     public double Top => Math.Round(Y, 5);
 
     [NotMapped]
     public double Left => Math.Round(X, 5);
-    }
+#endif
 }
+
+#if NETFRAMEWORK
+    }
+#endif