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/Server/ZB.MOM.WW.OtOpcUa.Host.IntegrationTests/DeployHappyPathTests.cs

@@ -18,6 +18,7 @@ public sealed class DeployHappyPathTests
 {
     private static CancellationToken Ct => TestContext.Current.CancellationToken;
 
+    /// <summary>Verifies that StartDeployment seals after both nodes apply.</summary>
     [Fact]
     public async Task StartDeployment_seals_after_both_nodes_apply()
     {
@@ -53,6 +54,7 @@ public sealed class DeployHappyPathTests
         nodeStates.ShouldAllBe(s => s.Status == NodeDeploymentStatus.Applied);
     }
 
+    /// <summary>Verifies that replaying dispatch to same revision is idempotent and a no-op.</summary>
     [Fact]
     public async Task Replaying_dispatch_to_same_revision_is_idempotent_no_op()
     {