docs(xmldoc): fill missing XML docs + strip tracking-ID comments across src

Adds <summary>/<param>/<returns>/<inheritdoc> where missing and removes
project bookkeeping IDs (task/tracking refs) from shipped code comments,
so the docs read cleanly and CommentChecker is quiet except for known
false positives (PLC/protocol terms, event/IEqualityComparer inheritdoc).
Doc/comment-only; no logic changed; solution builds clean.

src/Server/ZB.MOM.WW.OtOpcUa.Host/Health/HealthEndpoints.cs

@@ -14,6 +14,8 @@ public static class HealthEndpoints
     /// Registers the shared ZB.MOM.WW health probes. Tier semantics preserved: configdb + akka on
     /// ready+active; admin-leader on active only.
     /// </summary>
+    /// <param name="services">The service collection to register the health checks on.</param>
+    /// <returns>The same service collection, for chaining.</returns>
     public static IServiceCollection AddOtOpcUaHealth(this IServiceCollection services)
     {
         services.AddHealthChecks()
@@ -40,6 +42,7 @@ public static class HealthEndpoints
 
     /// <summary>Maps the OtOpcUa health check endpoints to the route builder.</summary>
     /// <param name="app">The endpoint route builder.</param>
+    /// <returns>The same endpoint route builder, for chaining.</returns>
     public static IEndpointRouteBuilder MapOtOpcUaHealth(this IEndpointRouteBuilder app)
     {
         app.MapZbHealth();