fix(historian): dead-letter poison events after maxAttempts (finding 002)

src/Server/ZB.MOM.WW.OtOpcUa.Runtime/Historian/AlarmHistorianOptions.cs

@@ -53,6 +53,10 @@ public sealed class AlarmHistorianOptions
     /// <summary>Days to retain dead-lettered rows before purge. Defaults to 30.</summary>
     public int DeadLetterRetentionDays { get; init; } = 30;
 
+    /// <summary>Maximum delivery attempts before a perpetually-retrying (poison) row is dead-lettered.
+    /// Defaults to 10 (matches <c>SqliteStoreAndForwardSink</c>'s <c>DefaultMaxAttempts</c>).</summary>
+    public int MaxAttempts { get; init; } = SqliteStoreAndForwardSink.DefaultMaxAttempts;
+
     /// <summary>Returns operator-facing misconfiguration warnings for an <c>Enabled</c> historian
     /// (empty when disabled or correctly configured). Pure — the registration logs each entry.</summary>
     /// <returns>Zero or more human-readable warning messages.</returns>
@@ -70,6 +74,8 @@ public sealed class AlarmHistorianOptions
             warnings.Add($"AlarmHistorian:Capacity is {Capacity} — must be > 0; the sink constructor will throw at startup.");
         if (DeadLetterRetentionDays <= 0)
             warnings.Add($"AlarmHistorian:DeadLetterRetentionDays is {DeadLetterRetentionDays} — must be > 0; dead-lettered rows would be purged on every drain tick.");
+        if (MaxAttempts <= 0)
+            warnings.Add($"AlarmHistorian:MaxAttempts is {MaxAttempts} — must be > 0; the sink constructor will throw at startup.");
         return warnings;
     }
 }

src/Server/ZB.MOM.WW.OtOpcUa.Runtime/ServiceCollectionExtensions.cs

@@ -93,7 +93,8 @@ public static class ServiceCollectionExtensions
                 Serilog.Log.Logger.ForContext<SqliteStoreAndForwardSink>(),
                 batchSize: opts.BatchSize,
                 capacity: opts.Capacity,
-                deadLetterRetention: TimeSpan.FromDays(opts.DeadLetterRetentionDays));
+                deadLetterRetention: TimeSpan.FromDays(opts.DeadLetterRetentionDays),
+                maxAttempts: opts.MaxAttempts);
             sink.StartDrainLoop(TimeSpan.FromSeconds(opts.DrainIntervalSeconds));
             return sink;
         });