feature: Prometheus Metrics, Supervisor Dashboard, and Promotion Retry Job

VigilCareRecordsAPI/Domain/Entities/PromotionAttempt.cs

@@ -0,0 +1,17 @@
+/// <summary>
+/// Tracks individual promotion attempts for a batch. Used by the
+/// PromotionRetryService to determine retry timing and attempt count.
+/// Each row represents one attempt (successful or failed).
+/// </summary>
+public class PromotionAttempt
+{
+    public Guid Id { get; set; }
+    public Guid BatchId { get; set; }
+    public int AttemptNumber { get; set; }
+    public bool Succeeded { get; set; }
+    public string? ErrorMessage { get; set; }
+    public DateTimeOffset AttemptedAt { get; set; }
+    public DateTimeOffset? NextRetryAt { get; set; }
+
+    public DigitizationBatch Batch { get; set; } = null!;
+}