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/Mapping/AggregateModeMapper.cs

@@ -25,7 +25,8 @@ internal static class AggregateModeMapper
     /// <summary>Maps an aggregate function to the gateway retrieval mode.</summary>
     /// <param name="aggregate">The driver-agnostic aggregate function.</param>
     /// <returns>The matching gateway <see cref="RetrievalMode"/>.</returns>
-    /// <exception cref="ArgumentOutOfRangeException">A future, unmapped enum member (fails the matrix guard).</exception>
+    /// <exception cref="HistoryAggregateNotSupportedException">A defined member the gateway has no retrieval mode for.</exception>
+    /// <exception cref="ArgumentOutOfRangeException">An undefined enum value.</exception>
     public static RetrievalMode ToRetrievalMode(HistoryAggregateType aggregate) => aggregate switch
     {
         HistoryAggregateType.Average => RetrievalMode.TimeWeightedAverage,
@@ -33,6 +34,10 @@ internal static class AggregateModeMapper
         HistoryAggregateType.Maximum => RetrievalMode.MaximumWithTime,
         HistoryAggregateType.Total => RetrievalMode.Integral,
         HistoryAggregateType.Count => RetrievalMode.Counter,
+        // Part 13 aggregates the gateway has no retrieval mode for (#285) — an UNDEFINED enum value is a
+        // programming error, but a defined-yet-unserved member is a normal client request the server
+        // answers with BadAggregateNotSupported.
+        _ when Enum.IsDefined(aggregate) => throw new HistoryAggregateNotSupportedException(aggregate),
         _ => throw new ArgumentOutOfRangeException(
             nameof(aggregate), aggregate, "Unmapped HistoryAggregateType — add a RetrievalMode mapping."),
     };