feat(data): record which event type each webhook processed

PatchNotes.Api/Routes/AdminReadRoutes.cs

@@ -253,6 +253,7 @@ private static void MapWebhookEvents(
                 .Select(e => new AdminWebhookEventDto
                 {
                     EventId = e.EventId,
+                    EventType = e.EventType,
                     ProcessedAt = e.ProcessedAt,
                 })
                 .ToListAsync();
@@ -333,5 +334,9 @@ public class AdminDigestEmailDto
 public class AdminWebhookEventDto
 {
     public required string EventId { get; set; }
+
+    /// <summary>Null for rows recorded before the column existed; it cannot be backfilled.</summary>
+    public string? EventType { get; set; }
+
     public DateTimeOffset ProcessedAt { get; set; }
 }

PatchNotes.Api/Webhooks/StripeWebhook.cs

@@ -108,6 +108,7 @@ public static WebApplication MapStripeWebhook(this WebApplication app)
                     db.ProcessedWebhookEvents.Add(new ProcessedWebhookEvent
                     {
                         EventId = stripeEvent.Id,
+                        EventType = stripeEvent.Type,
                         ProcessedAt = DateTimeOffset.UtcNow
                     });
                     await db.SaveChangesAsync();

PatchNotes.Api/Webhooks/StytchWebhook.cs

@@ -216,6 +216,8 @@ public static WebApplication MapStytchWebhook(this WebApplication app)
             db.ProcessedWebhookEvents.Add(new ProcessedWebhookEvent
             {
                 EventId = svixId,
+                // Stytch splits this across two fields; joined to read like Stripe's dotted types.
+                EventType = $"{stytchEvent.object_type}.{stytchEvent.action}",
                 ProcessedAt = DateTimeOffset.UtcNow
             });
             await db.SaveChangesAsync();