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/Drivers/ZB.MOM.WW.OtOpcUa.Driver.Galaxy.Tests/Health/HostStatusAggregatorTests.cs

@@ -15,6 +15,7 @@ public sealed class HostStatusAggregatorTests
     private static HostConnectivityStatus Status(string host, HostState state) =>
         new(host, state, DateTime.UtcNow);
 
+    /// <summary>Verifies that snapshot is empty when nothing is tracked.</summary>
     [Fact]
     public void Snapshot_Empty_WhenNothingTracked()
     {
@@ -22,6 +23,7 @@ public sealed class HostStatusAggregatorTests
         agg.Snapshot().ShouldBeEmpty();
     }
 
+    /// <summary>Verifies that updating a new host fires a change event with Unknown as previous state.</summary>
     [Fact]
     public void Update_NewHost_FiresChange_PreviousIsUnknown()
     {
@@ -37,6 +39,7 @@ public sealed class HostStatusAggregatorTests
         captured[0].NewState.ShouldBe(HostState.Running);
     }
 
+    /// <summary>Verifies that updating to the same state does not fire a change event.</summary>
     [Fact]
     public void Update_SameState_DoesNotFire()
     {
@@ -51,6 +54,7 @@ public sealed class HostStatusAggregatorTests
         captured.ShouldBeEmpty();
     }
 
+    /// <summary>Verifies that state transitions fire change events with correct old and new states.</summary>
     [Fact]
     public void Update_StateTransition_FiresChangeWithCorrectPreviousAndNew()
     {
@@ -67,6 +71,7 @@ public sealed class HostStatusAggregatorTests
         captured[0].NewState.ShouldBe(HostState.Stopped);
     }
 
+    /// <summary>Verifies that snapshot reflects every upserted host.</summary>
     [Fact]
     public void Snapshot_ReflectsEveryUpsertedHost()
     {
@@ -82,6 +87,7 @@ public sealed class HostStatusAggregatorTests
         snap.First(s => s.HostName == "PlatformB").State.ShouldBe(HostState.Stopped);
     }
 
+    /// <summary>Verifies that host name comparison is case-insensitive.</summary>
     [Fact]
     public void Update_HostNameComparison_IsCaseInsensitive()
     {
@@ -98,6 +104,7 @@ public sealed class HostStatusAggregatorTests
         agg.Snapshot().Count.ShouldBe(1);
     }
 
+    /// <summary>Verifies that removing a tracked host returns true and drops it from snapshot.</summary>
     [Fact]
     public void Remove_TrackedHost_ReturnsTrue_AndDropsFromSnapshot()
     {
@@ -107,6 +114,7 @@ public sealed class HostStatusAggregatorTests
         agg.Snapshot().ShouldBeEmpty();
     }
 
+    /// <summary>Verifies that removing an unknown host returns false.</summary>
     [Fact]
     public void Remove_UnknownHost_ReturnsFalse()
     {
@@ -114,6 +122,7 @@ public sealed class HostStatusAggregatorTests
         agg.Remove("Nope").ShouldBeFalse();
     }
 
+    /// <summary>Verifies that concurrent updates do not corrupt the internal dictionary.</summary>
     [Fact]
     public void ConcurrentUpdates_DoNotCorruptDictionary()
     {