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.Host/Health/AdminRoleLeaderHealthCheck.cs

@@ -13,11 +13,17 @@ public sealed class AdminRoleLeaderHealthCheck : IHealthCheck
 {
     private readonly IClusterRoleInfo _roleInfo;
 
+    /// <summary>Initializes a new instance of the AdminRoleLeaderHealthCheck class.</summary>
+    /// <param name="roleInfo">The cluster role information provider.</param>
     public AdminRoleLeaderHealthCheck(IClusterRoleInfo roleInfo)
     {
         _roleInfo = roleInfo;
     }
 
+    /// <summary>Checks the health status of the admin role leader.</summary>
+    /// <param name="context">The health check context.</param>
+    /// <param name="cancellationToken">The cancellation token.</param>
+    /// <returns>A task representing the health check operation.</returns>
     public Task<HealthCheckResult> CheckHealthAsync(HealthCheckContext context, CancellationToken cancellationToken = default)
     {
         if (!_roleInfo.HasRole("admin"))

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

@@ -8,11 +8,20 @@ public sealed class AkkaClusterHealthCheck : IHealthCheck
 {
     private readonly ActorSystem _system;
 
+    /// <summary>
+    /// Initializes a new instance of the AkkaClusterHealthCheck class.
+    /// </summary>
+    /// <param name="system">The Akka actor system to check cluster health for.</param>
     public AkkaClusterHealthCheck(ActorSystem system)
     {
         _system = system;
     }
 
+    /// <summary>
+    /// Checks the health of the Akka cluster asynchronously.
+    /// </summary>
+    /// <param name="context">The health check context.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
     public Task<HealthCheckResult> CheckHealthAsync(HealthCheckContext context, CancellationToken cancellationToken = default)
     {
         var cluster = Akka.Cluster.Cluster.Get(_system);

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

@@ -8,11 +8,20 @@ public sealed class DatabaseHealthCheck : IHealthCheck
 {
     private readonly IDbContextFactory<OtOpcUaConfigDbContext> _dbFactory;
 
+    /// <summary>
+    /// Initializes a new instance of the <see cref="DatabaseHealthCheck"/> class.
+    /// </summary>
+    /// <param name="dbFactory">The database context factory for the config database.</param>
     public DatabaseHealthCheck(IDbContextFactory<OtOpcUaConfigDbContext> dbFactory)
     {
         _dbFactory = dbFactory;
     }
 
+    /// <summary>
+    /// Checks the health of the configuration database.
+    /// </summary>
+    /// <param name="context">The health check context.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
     public async Task<HealthCheckResult> CheckHealthAsync(HealthCheckContext context, CancellationToken cancellationToken = default)
     {
         try

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

@@ -13,6 +13,7 @@ public static class HealthEndpoints
     /// probes. Mirrors ScadaLink's three-tier pattern: <c>ready</c> = boot ok; <c>active</c> =
     /// fully serving traffic; <c>healthz</c> = bare process liveness.
     /// </summary>
+    /// <param name="services">The service collection to register health checks with.</param>
     public static IServiceCollection AddOtOpcUaHealth(this IServiceCollection services)
     {
         services.AddHealthChecks()
@@ -22,6 +23,8 @@ public static class HealthEndpoints
         return services;
     }
 
+    /// <summary>Maps the OtOpcUa health check endpoints to the route builder.</summary>
+    /// <param name="app">The endpoint route builder.</param>
     public static IEndpointRouteBuilder MapOtOpcUaHealth(this IEndpointRouteBuilder app)
     {
         // AllowAnonymous on all three — Traefik / k8s liveness probes / load-balancers