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.

src/Server/ZB.MOM.WW.OtOpcUa.ControlPlane/Redundancy/RedundancyStateActor.cs

@@ -27,13 +27,20 @@ public sealed class RedundancyStateActor : ReceiveActor, IWithTimers
     private readonly Action<object>? _broadcastOverride;
     private bool _dirty;
 
+    /// <summary>Gets the timer scheduler for this actor.</summary>
     public ITimerScheduler Timers { get; set; } = null!;
 
+    /// <summary>Creates a Props for creating a RedundancyStateActor.</summary>
+    /// <param name="broadcast">Optional broadcast override for testing.</param>
+    /// <returns>Props for actor creation.</returns>
     public static Props Props(Action<object>? broadcast = null) =>
         Akka.Actor.Props.Create(() => new RedundancyStateActor(broadcast));
 
+    /// <summary>Initializes a new instance of RedundancyStateActor with no broadcast override.</summary>
     public RedundancyStateActor() : this(broadcast: null) { }
 
+    /// <summary>Initializes a new instance of RedundancyStateActor.</summary>
+    /// <param name="broadcast">Optional broadcast override for testing.</param>
     public RedundancyStateActor(Action<object>? broadcast)
     {
         _cluster = Akka.Cluster.Cluster.Get(Context.System);
@@ -47,6 +54,7 @@ public sealed class RedundancyStateActor : ReceiveActor, IWithTimers
         Receive<RecomputeNow>(_ => PublishIfDirty());
     }
 
+    /// <inheritdoc />
     protected override void PreStart()
     {
         _cluster.Subscribe(
@@ -58,6 +66,7 @@ public sealed class RedundancyStateActor : ReceiveActor, IWithTimers
             typeof(ClusterEvent.ReachabilityEvent));
     }
 
+    /// <inheritdoc />
     protected override void PostStop() => _cluster.Unsubscribe(Self);
 
     private void MarkDirty()

src/Server/ZB.MOM.WW.OtOpcUa.ControlPlane/Redundancy/ServiceLevelCalculator.cs

@@ -22,6 +22,9 @@ public readonly record struct NodeHealthInputs(
 /// </summary>
 public static class ServiceLevelCalculator
 {
+    /// <summary>Computes the service level (0-255) based on node health inputs.</summary>
+    /// <param name="h">The node health inputs including cluster state, database reachability, and probe status.</param>
+    /// <returns>A service level byte value (0-255) indicating node authority, where higher values indicate more authoritative nodes.</returns>
     public static byte Compute(NodeHealthInputs h)
     {
         if (h.MemberState is not (MemberStatus.Up or MemberStatus.Joining))