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.OpcUaClient.Tests/OpcUaClientAlarmTests.cs

@@ -7,6 +7,9 @@ namespace ZB.MOM.WW.OtOpcUa.Driver.OpcUaClient.Tests;
 [Trait("Category", "Unit")]
 public sealed class OpcUaClientAlarmTests
 {
+    /// <summary>Verifies that MapSeverity buckets per OPC UA Part 9 guidance.</summary>
+    /// <param name="opcSev">The OPC UA severity value (1–1000).</param>
+    /// <param name="expected">The expected mapped alarm severity.</param>
     [Theory]
     [InlineData((ushort)1, AlarmSeverity.Low)]
     [InlineData((ushort)200, AlarmSeverity.Low)]
@@ -21,6 +24,7 @@ public sealed class OpcUaClientAlarmTests
         OpcUaClientDriver.MapSeverity(opcSev).ShouldBe(expected);
     }
 
+    /// <summary>Verifies that MapSeverity zero maps to Low.</summary>
     [Fact]
     public void MapSeverity_zero_maps_to_Low()
     {
@@ -28,6 +32,7 @@ public sealed class OpcUaClientAlarmTests
         OpcUaClientDriver.MapSeverity(0).ShouldBe(AlarmSeverity.Low);
     }
 
+    /// <summary>Verifies that SubscribeAlarmsAsync without initialize throws InvalidOperationException.</summary>
     [Fact]
     public async Task SubscribeAlarmsAsync_without_initialize_throws_InvalidOperationException()
     {
@@ -36,6 +41,7 @@ public sealed class OpcUaClientAlarmTests
             await drv.SubscribeAlarmsAsync([], TestContext.Current.CancellationToken));
     }
 
+    /// <summary>Verifies that UnsubscribeAlarmsAsync with unknown handle is noop.</summary>
     [Fact]
     public async Task UnsubscribeAlarmsAsync_with_unknown_handle_is_noop()
     {
@@ -44,6 +50,7 @@ public sealed class OpcUaClientAlarmTests
         await drv.UnsubscribeAlarmsAsync(new FakeAlarmHandle(), TestContext.Current.CancellationToken);
     }
 
+    /// <summary>Verifies that AcknowledgeAsync without initialize throws InvalidOperationException.</summary>
     [Fact]
     public async Task AcknowledgeAsync_without_initialize_throws_InvalidOperationException()
     {
@@ -54,6 +61,7 @@ public sealed class OpcUaClientAlarmTests
                 TestContext.Current.CancellationToken));
     }
 
+    /// <summary>Verifies that AcknowledgeAsync with empty batch is noop even without init.</summary>
     [Fact]
     public async Task AcknowledgeAsync_with_empty_batch_is_noop_even_without_init()
     {
@@ -65,6 +73,7 @@ public sealed class OpcUaClientAlarmTests
 
     private sealed class FakeAlarmHandle : IAlarmSubscriptionHandle
     {
+        /// <summary>Gets the diagnostic identifier for this alarm handle.</summary>
         public string DiagnosticId => "fake-alarm";
     }
 }