Frontend gaps fill work. Testing fixes work. Auditing in progress.

src/Notifier/StellaOps.Notifier/StellaOps.Notifier.WebService/Contracts/DeliveryContracts.cs

@@ -0,0 +1,109 @@
+namespace StellaOps.Notifier.WebService.Contracts;
+
+/// <summary>
+/// API contracts for delivery history and retry endpoints.
+/// Sprint: SPRINT_20251229_018b_FE_notification_delivery_audit
+/// Task: NOTIFY-016
+/// </summary>
+
+/// <summary>
+/// Response for delivery listing.
+/// </summary>
+public sealed record DeliveryListResponse
+{
+    public required IReadOnlyList<DeliveryResponse> Items { get; init; }
+    public required int Total { get; init; }
+    public string? ContinuationToken { get; init; }
+}
+
+/// <summary>
+/// Individual delivery response.
+/// </summary>
+public sealed record DeliveryResponse
+{
+    public required string DeliveryId { get; init; }
+    public required string TenantId { get; init; }
+    public required string RuleId { get; init; }
+    public required string ChannelId { get; init; }
+    public string? EventId { get; init; }
+    public string? EventKind { get; init; }
+    public string? Target { get; init; }
+    public required string Status { get; init; }
+    public required IReadOnlyList<DeliveryAttemptResponse> Attempts { get; init; }
+    public required int RetryCount { get; init; }
+    public string? NextRetryAt { get; init; }
+    public string? Subject { get; init; }
+    public string? ErrorMessage { get; init; }
+    public required string CreatedAt { get; init; }
+    public string? SentAt { get; init; }
+    public string? CompletedAt { get; init; }
+}
+
+/// <summary>
+/// Individual delivery attempt response.
+/// </summary>
+public sealed record DeliveryAttemptResponse
+{
+    public required int AttemptNumber { get; init; }
+    public required string Timestamp { get; init; }
+    public required string Status { get; init; }
+    public int? StatusCode { get; init; }
+    public string? ErrorMessage { get; init; }
+    public int? ResponseTimeMs { get; init; }
+}
+
+/// <summary>
+/// Request to retry a failed delivery.
+/// </summary>
+public sealed record DeliveryRetryRequest
+{
+    public string? ForceChannel { get; init; }
+    public bool BypassThrottle { get; init; }
+    public string? Reason { get; init; }
+}
+
+/// <summary>
+/// Response from retry operation.
+/// </summary>
+public sealed record DeliveryRetryResponse
+{
+    public required string DeliveryId { get; init; }
+    public required bool Retried { get; init; }
+    public required int NewAttemptNumber { get; init; }
+    public required string ScheduledAt { get; init; }
+    public string? Message { get; init; }
+}
+
+/// <summary>
+/// Delivery statistics response.
+/// </summary>
+public sealed record DeliveryStatsResponse
+{
+    public required int TotalSent { get; init; }
+    public required int TotalFailed { get; init; }
+    public required int TotalThrottled { get; init; }
+    public required int TotalPending { get; init; }
+    public required double AvgDeliveryTimeMs { get; init; }
+    public required double SuccessRate { get; init; }
+    public required string Period { get; init; }
+    public required IReadOnlyDictionary<string, ChannelStatsResponse> ByChannel { get; init; }
+    public required IReadOnlyDictionary<string, EventKindStatsResponse> ByEventKind { get; init; }
+}
+
+/// <summary>
+/// Statistics by channel.
+/// </summary>
+public sealed record ChannelStatsResponse
+{
+    public required int Sent { get; init; }
+    public required int Failed { get; init; }
+}
+
+/// <summary>
+/// Statistics by event kind.
+/// </summary>
+public sealed record EventKindStatsResponse
+{
+    public required int Sent { get; init; }
+    public required int Failed { get; init; }
+}