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.FOCAS.IntegrationTests/FocasSimFixture.cs

@@ -23,7 +23,10 @@ public sealed class FocasSimFixture : IAsyncDisposable
     private const string DefaultHost = "localhost";
     private const int DefaultPort = 8193;
 
+    /// <summary>Gets the hostname or IP address of the focas-mock simulator.</summary>
     public string Host { get; }
+
+    /// <summary>Gets the TCP port of the focas-mock simulator.</summary>
     public int Port { get; }
 
     /// <summary>focas-mock profile stem the fixture should load (e.g. <c>fwlib30i64</c>,
@@ -37,6 +40,10 @@ public sealed class FocasSimFixture : IAsyncDisposable
     /// <summary>Non-null when the mock probe failed — tests skip with this reason.</summary>
     public string? SkipReason { get; }
 
+    /// <summary>
+    ///     Initializes a new instance of the <see cref="FocasSimFixture"/> class by probing the focas-mock
+    ///     simulator endpoint. Reads the endpoint and profile from environment variables or uses defaults.
+    /// </summary>
     public FocasSimFixture()
     {
         var endpoint = Environment.GetEnvironmentVariable(EndpointEnvVar) ?? $"{DefaultHost}:{DefaultPort}";
@@ -66,6 +73,7 @@ public sealed class FocasSimFixture : IAsyncDisposable
         }
     }
 
+    /// <summary>Disposes the fixture and releases any held resources.</summary>
     public ValueTask DisposeAsync() => ValueTask.CompletedTask;
 
     // ---- Admin API helpers ----
@@ -75,23 +83,33 @@ public sealed class FocasSimFixture : IAsyncDisposable
     ///     (<c>fwlib30i64</c>) or the OtOpcUa-style alias (<c>ThirtyOne_i</c>);
     ///     focas-mock's <c>PROFILE_ALIASES</c> resolves both.
     /// </summary>
+    /// <param name="profileName">The DLL-stem name or OtOpcUa-style alias of the profile to load.</param>
+    /// <param name="ct">Cancellation token for the operation.</param>
     public Task<JsonElement> LoadProfileAsync(string profileName, CancellationToken ct = default) =>
         SendAdminAsync("mock_load_profile", new { profile = profileName }, ct);
 
     /// <summary>Deep-merge <paramref name="state"/> into the mock's current state.</summary>
+    /// <param name="state">The state object to deep-merge into the mock's current state.</param>
+    /// <param name="ct">Cancellation token for the operation.</param>
     public Task<JsonElement> PatchStateAsync(object state, CancellationToken ct = default) =>
         SendAdminAsync("mock_patch", new { state }, ct);
 
     /// <summary>Reset the mock to the selected profile's default state.</summary>
+    /// <param name="ct">Cancellation token for the operation.</param>
     public Task<JsonElement> ResetAsync(CancellationToken ct = default) =>
         SendAdminAsync("mock_reset", new { }, ct);
 
     /// <summary>Install a time-scheduled alarm raise / clear sequence.</summary>
+    /// <param name="sequence">The alarm sequence events to schedule.</param>
+    /// <param name="ct">Cancellation token for the operation.</param>
     public Task<JsonElement> ScheduleAlarmsAsync(IEnumerable<object> sequence, CancellationToken ct = default) =>
         SendAdminAsync("mock_schedule_alarms", new { sequence }, ct);
 
     /// <summary>Low-level JSON round-trip. One TCP connection per call — matches
     /// how the shim talks to the mock; simpler than pooling.</summary>
+    /// <param name="method">The admin method name to invoke.</param>
+    /// <param name="params">The parameters object to send with the request.</param>
+    /// <param name="ct">Cancellation token for the operation.</param>
     public async Task<JsonElement> SendAdminAsync(string method, object @params, CancellationToken ct = default)
     {
         using var client = new TcpClient();