docs: backfill XML documentation across 756 files

Adds <summary>, <param>, <typeparam>, and <inheritdoc/> tags to public
members surfaced by commentchecker — resolves 5,847 of 5,869 issues
(99.6%) across three /fixdocs passes.

tests/Core/ZB.MOM.WW.OtOpcUa.Core.Abstractions.Tests/Alarms/AlarmConditionInfoTests.cs

@@ -12,6 +12,7 @@ namespace ZB.MOM.WW.OtOpcUa.Core.Abstractions.Tests.Alarms;
 /// </summary>
 public sealed class AlarmConditionInfoTests
 {
+    /// <summary>Verifies that the legacy three-argument constructor still compiles and defaults refs to null.</summary>
     [Fact]
     public void LegacyThreeArgConstructor_StillCompiles_AndDefaultsRefsToNull()
     {
@@ -30,6 +31,7 @@ public sealed class AlarmConditionInfoTests
         info.AckMsgWriteRef.ShouldBeNull();
     }
 
+    /// <summary>Verifies that the full constructor populates all five sub-attribute references.</summary>
     [Fact]
     public void FullConstructor_PopulatesAllFiveSubAttributeRefs()
     {
@@ -50,6 +52,7 @@ public sealed class AlarmConditionInfoTests
         info.AckMsgWriteRef.ShouldBe("Tank1.HiAlarm.AckMsg");
     }
 
+    /// <summary>Verifies that record equality compares all eight fields.</summary>
     [Fact]
     public void RecordEquality_ComparesAllEightFields()
     {
@@ -66,6 +69,7 @@ public sealed class AlarmConditionInfoTests
         a.ShouldBe(b);
     }
 
+    /// <summary>Verifies that records are distinct when any reference differs.</summary>
     [Fact]
     public void RecordEquality_DistinctWhenAnyRefDiffers()
     {
@@ -78,6 +82,7 @@ public sealed class AlarmConditionInfoTests
         baseInfo.ShouldNotBe(differingAckRef);
     }
 
+    /// <summary>Verifies that with-expressions allow partial updates.</summary>
     [Fact]
     public void WithExpression_AllowsPartialUpdates()
     {