feat(history): full Part 13 aggregate set; unsupported-by-backend aggregates answer BadAggregateNotSupported (#285)

Claude-Session: https://claude.ai/code/session_01Ef2ozxS7QPanGT8uoATbTe

src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.Historian.Gateway/GatewayHistorianDataSource.cs

@@ -79,11 +79,13 @@ public sealed class GatewayHistorianDataSource : IHistorianDataSource, IAsyncDis
         string fullReference, DateTime startUtc, DateTime endUtc, TimeSpan interval,
         HistoryAggregateType aggregate, CancellationToken cancellationToken)
     {
+        // Mapped OUTSIDE the failure-recording try: an aggregate the gateway has no mode for is a client
+        // request the server answers BadAggregateNotSupported, not a backend fault to count (#285).
+        var mode = AggregateModeMapper.ToRetrievalMode(aggregate);
         try
         {
             // Total/Count are now native gateway retrieval modes — no client-side scaling
             // (unlike the Wonderware path that derived Total as Average × interval-seconds).
-            var mode = AggregateModeMapper.ToRetrievalMode(aggregate);
             var buckets = new List<HistorianAggregateSample>();
             await foreach (var bucket in _client
                 .ReadAggregateAsync(fullReference, startUtc, endUtc, mode, interval, cancellationToken)