feat(auditlog): ParentExecutionId column on AuditEvent + central AuditLog

src/ScadaLink.Commons/Entities/Audit/AuditEvent.cs

@@ -33,6 +33,13 @@ public sealed record AuditEvent
     /// </summary>
     public Guid? ExecutionId { get; init; }
 
+    /// <summary>
+    /// <see cref="ExecutionId"/> of the execution that spawned this run, when this
+    /// run was spawned by another; null for top-level runs. Lets a spawned
+    /// execution point back at its spawner for cross-run correlation.
+    /// </summary>
+    public Guid? ParentExecutionId { get; init; }
+
     /// <summary>Site id where the action originated; null for central-direct events.</summary>
     public string? SourceSiteId { get; init; }