WIP: Record history

DiunaBI.Domain/Entities/RecordHistory.cs

@@ -0,0 +1,37 @@
+using System;
+
+namespace DiunaBI.Domain.Entities;
+
+public enum RecordChangeType
+{
+    Created = 1,
+    Updated = 2,
+    Deleted = 3
+}
+
+public class RecordHistory
+{
+    public Guid Id { get; set; }
+
+    // Reference to the original record
+    public Guid RecordId { get; set; }
+    public Guid LayerId { get; set; }
+
+    // When and who
+    public DateTime ChangedAt { get; set; }
+    public Guid ChangedById { get; set; }
+    public User? ChangedBy { get; set; }
+
+    // Type of change
+    public RecordChangeType ChangeType { get; set; }
+
+    // Snapshot of record state at this point
+    public string Code { get; set; } = string.Empty;
+    public string? Desc1 { get; set; }
+
+    // Comma-separated list of fields that changed (e.g., "Code,Desc1")
+    public string? ChangedFields { get; set; }
+
+    // JSON object with detailed changes: {"Code": {"old": "A", "new": "B"}}
+    public string? ChangesSummary { get; set; }
+}