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.AbCip.Tests/AbCipSubscriptionTests.cs

@@ -20,6 +20,7 @@ public sealed class AbCipSubscriptionTests
         return (drv, factory);
     }
 
+    /// <summary>Verifies that the initial poll raises OnDataChange events for every subscribed tag.</summary>
     [Fact]
     public async Task Initial_poll_raises_OnDataChange_for_every_tag()
     {
@@ -45,6 +46,7 @@ public sealed class AbCipSubscriptionTests
         await drv.UnsubscribeAsync(handle, CancellationToken.None);
     }
 
+    /// <summary>Verifies that unchanged values raise OnDataChange only once (on initial poll).</summary>
     [Fact]
     public async Task Unchanged_value_raises_only_once()
     {
@@ -63,6 +65,7 @@ public sealed class AbCipSubscriptionTests
         events.Count.ShouldBe(1);
     }
 
+    /// <summary>Verifies that value changes between polls raise OnDataChange events.</summary>
     [Fact]
     public async Task Value_change_between_polls_raises_OnDataChange()
     {
@@ -85,6 +88,7 @@ public sealed class AbCipSubscriptionTests
         events.Last().Snapshot.Value.ShouldBe(200);
     }
 
+    /// <summary>Verifies that unsubscribe halts polling and no further events are raised.</summary>
     [Fact]
     public async Task Unsubscribe_halts_polling()
     {
@@ -107,6 +111,7 @@ public sealed class AbCipSubscriptionTests
         events.Count.ShouldBe(afterUnsub);
     }
 
+    /// <summary>Verifies that polling intervals below 100ms are floored to the minimum.</summary>
     [Fact]
     public async Task Interval_below_100ms_is_floored()
     {
@@ -127,6 +132,7 @@ public sealed class AbCipSubscriptionTests
         events.Count.ShouldBe(1);
     }
 
+    /// <summary>Verifies that ShutdownAsync cancels all active subscriptions.</summary>
     [Fact]
     public async Task ShutdownAsync_cancels_active_subscriptions()
     {
@@ -147,6 +153,7 @@ public sealed class AbCipSubscriptionTests
         events.Count.ShouldBe(afterShutdown);
     }
 
+    /// <summary>Verifies that subscriptions on UDT members use the synthesized full reference.</summary>
     [Fact]
     public async Task Subscription_on_UDT_member_uses_synthesised_full_reference()
     {