Migrate historian from SQL to aahClientManaged SDK and resolve all OPC UA Part 11 gaps

Replace direct SQL queries against Historian Runtime database with the Wonderware
Historian managed SDK (ArchestrA.HistorianAccess). Add HistoryServerCapabilities node,
AggregateFunctions folder, continuation points, ReadAtTime interpolation, ReturnBounds,
ReadModified rejection, HistoricalDataConfiguration per node, historical event access,
and client-side StandardDeviation aggregate support. Remove screenshot tests.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/ZB.MOM.WW.LmxOpcUa.Client.Shared/Helpers/AggregateTypeMapper.cs

@@ -21,6 +21,7 @@ public static class AggregateTypeMapper
             AggregateType.Count => ObjectIds.AggregateFunction_Count,
             AggregateType.Start => ObjectIds.AggregateFunction_Start,
             AggregateType.End => ObjectIds.AggregateFunction_End,
+            AggregateType.StandardDeviation => ObjectIds.AggregateFunction_StandardDeviationPopulation,
             _ => throw new ArgumentOutOfRangeException(nameof(aggregate), aggregate, "Unknown AggregateType value.")
         };
     }

src/ZB.MOM.WW.LmxOpcUa.Client.Shared/Models/AggregateType.cs

@@ -21,5 +21,8 @@ public enum AggregateType
     Start,
 
     /// <summary>Last value in the interval.</summary>
-    End
+    End,
+
+    /// <summary>Population standard deviation of values in the interval.</summary>
+    StandardDeviation
 }