perf(mtconnect): stream sample-chunk parsing through XmlReader; no per-chunk document tree

tests/Drivers/ZB.MOM.WW.OtOpcUa.Driver.MTConnect.Tests/MTConnectStreamsParseTests.cs

@@ -1061,6 +1061,30 @@ public sealed class MTConnectStreamsParseTests
         observation.DataItemId.ShouldBe("ds");
     }
 
+    [Fact]
+    public void The_indentation_between_child_entries_is_not_part_of_the_value()
+    {
+        // The parser reads forward-only off an XmlReader, and the value it reports is the
+        // concatenation of the text it meets on the way. That concatenation only matches what the
+        // XDocument it replaced reported because whitespace-only text nodes are dropped
+        // (XmlReaderSettings.IgnoreWhitespace, which is what XDocument.Load defaulted to) — so
+        // entries separated by a line break must still read "12", never "1\n  2". Nothing else in
+        // this file can tell the two settings apart: the DATA_SET case above writes its entries
+        // adjacent, and every other observation is a single text node that Trim() cleans up either
+        // way. The observation index codes a structured observation BadNotSupported, so the value
+        // itself is not what matters here — the setting is, and this is the only test that moves
+        // when it changes.
+        var result = MTConnectStreamsParser.Parse(StreamsDocument(
+            """
+            <Events><PathFeedrateOverride dataItemId="ds" timestamp="2026-07-24T12:00:00Z" count="2">
+              <Entry key="V1">1</Entry>
+              <Entry key="V2">2</Entry>
+            </PathFeedrateOverride></Events>
+            """));
+
+        result.Observations.ShouldHaveSingleItem().Value.ShouldBe("12");
+    }
+
     [Fact]
     public void A_plain_text_observation_containing_spaces_is_NOT_flagged_structured()
     {