docs: complete XML doc comments via fixdocs (2757 to 131 findings)

Add missing <returns>/<param>/<summary>/<typeparam> tags and clean up
misused inheritdoc across 481 files so the documented API surface is
complete. Documentation-only (zero code lines changed). The 131 remaining
findings are inheritdoc-style warnings deliberately left to preserve
hand-written implementation rationale (plan-decision notes, race-condition
explanations).

tests/Core/ZB.MOM.WW.OtOpcUa.Core.Tests/DriverHostTests.cs

@@ -10,10 +10,10 @@ public sealed class DriverHostTests
 {
     private sealed class StubDriver(string id, bool failInit = false) : IDriver
     {
-        /// <summary>Gets the driver instance identifier.</summary>
+        /// <inheritdoc />
         public string DriverInstanceId { get; } = id;
 
-        /// <summary>Gets the driver type name.</summary>
+        /// <inheritdoc />
         public string DriverType => "Stub";
 
         /// <summary>Gets a value indicating whether the driver has been initialized.</summary>
@@ -22,9 +22,7 @@ public sealed class DriverHostTests
         /// <summary>Gets a value indicating whether the driver has been shut down.</summary>
         public bool ShutDown { get; private set; }
 
-        /// <summary>Initializes the driver asynchronously.</summary>
-        /// <param name="_">Configuration data (unused in stub).</param>
-        /// <param name="ct">The cancellation token.</param>
+        /// <inheritdoc />
         public Task InitializeAsync(string _, CancellationToken ct)
         {
             if (failInit) throw new InvalidOperationException("boom");
@@ -32,28 +30,25 @@ public sealed class DriverHostTests
             return Task.CompletedTask;
         }
 
-        /// <summary>Reinitializes the driver asynchronously.</summary>
-        /// <param name="_">Configuration data (unused in stub).</param>
-        /// <param name="ct">The cancellation token.</param>
+        /// <inheritdoc />
         public Task ReinitializeAsync(string _, CancellationToken ct) => Task.CompletedTask;
 
-        /// <summary>Shuts down the driver asynchronously.</summary>
-        /// <param name="ct">The cancellation token.</param>
+        /// <inheritdoc />
         public Task ShutdownAsync(CancellationToken ct) { ShutDown = true; return Task.CompletedTask; }
 
-        /// <summary>Gets the current health status of the driver.</summary>
+        /// <inheritdoc />
         public DriverHealth GetHealth() =>
             new(Initialized ? DriverState.Healthy : DriverState.Unknown, null, null);
 
-        /// <summary>Gets the memory footprint of the driver.</summary>
+        /// <inheritdoc />
         public long GetMemoryFootprint() => 0;
 
-        /// <summary>Flushes optional caches asynchronously.</summary>
-        /// <param name="ct">The cancellation token.</param>
+        /// <inheritdoc />
         public Task FlushOptionalCachesAsync(CancellationToken ct) => Task.CompletedTask;
     }
 
     /// <summary>Verifies that registering a driver initializes it and tracks its health.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Register_initializes_driver_and_tracks_health()
     {
@@ -68,6 +63,7 @@ public sealed class DriverHostTests
     }
 
     /// <summary>Verifies that registration rethrows initialization failures but keeps the driver registered.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Register_rethrows_init_failure_but_keeps_driver_registered()
     {
@@ -81,6 +77,7 @@ public sealed class DriverHostTests
     }
 
     /// <summary>Verifies that duplicate driver registration throws an exception.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Duplicate_registration_throws()
     {
@@ -92,6 +89,7 @@ public sealed class DriverHostTests
     }
 
     /// <summary>Verifies that unregistering a driver shuts it down and removes it.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Unregister_shuts_down_and_removes()
     {
@@ -113,6 +111,7 @@ public sealed class DriverHostTests
     ///     The driver awaits an unsettled TaskCompletionSource so it does not introduce its
     ///     own capture — only DriverHost's await of the returned Task can drive a post.
     /// </summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task RegisterAsync_Does_Not_Capture_SynchronizationContext()
     {
@@ -137,6 +136,7 @@ public sealed class DriverHostTests
     }
 
     /// <summary>Verifies that UnregisterAsync does not capture the synchronization context.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task UnregisterAsync_Does_Not_Capture_SynchronizationContext()
     {
@@ -165,6 +165,7 @@ public sealed class DriverHostTests
     }
 
     /// <summary>Verifies that DisposeAsync does not capture the synchronization context.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task DisposeAsync_Does_Not_Capture_SynchronizationContext()
     {
@@ -225,34 +226,28 @@ public sealed class DriverHostTests
     /// <summary>Driver whose Initialize / Shutdown completions are caller-controlled via TCS.</summary>
     private sealed class TcsDriver(string id, TaskCompletionSource initTcs, TaskCompletionSource? shutdownTcs = null) : IDriver
     {
-        /// <summary>Gets the driver instance identifier.</summary>
+        /// <inheritdoc />
         public string DriverInstanceId { get; } = id;
 
-        /// <summary>Gets the driver type name.</summary>
+        /// <inheritdoc />
         public string DriverType => "Tcs";
 
-        /// <summary>Initializes the driver asynchronously.</summary>
-        /// <param name="_">Configuration data (unused in TCS driver).</param>
-        /// <param name="ct">The cancellation token.</param>
+        /// <inheritdoc />
         public Task InitializeAsync(string _, CancellationToken ct) => initTcs.Task;
 
-        /// <summary>Reinitializes the driver asynchronously.</summary>
-        /// <param name="_">Configuration data (unused in TCS driver).</param>
-        /// <param name="ct">The cancellation token.</param>
+        /// <inheritdoc />
         public Task ReinitializeAsync(string _, CancellationToken ct) => Task.CompletedTask;
 
-        /// <summary>Shuts down the driver asynchronously.</summary>
-        /// <param name="ct">The cancellation token.</param>
+        /// <inheritdoc />
         public Task ShutdownAsync(CancellationToken ct) => (shutdownTcs ?? CompletedTcs).Task;
 
-        /// <summary>Gets the current health status of the driver.</summary>
+        /// <inheritdoc />
         public DriverHealth GetHealth() => new(DriverState.Healthy, null, null);
 
-        /// <summary>Gets the memory footprint of the driver.</summary>
+        /// <inheritdoc />
         public long GetMemoryFootprint() => 0;
 
-        /// <summary>Flushes optional caches asynchronously.</summary>
-        /// <param name="ct">The cancellation token.</param>
+        /// <inheritdoc />
         public Task FlushOptionalCachesAsync(CancellationToken ct) => Task.CompletedTask;
 
         private static readonly TaskCompletionSource CompletedTcs = MakeCompleted();
@@ -271,7 +266,6 @@ public sealed class DriverHostTests
         public int PostCount;
         public int SendCount;
 
-        /// <summary>Posts a callback to the work queue.</summary>
         /// <inheritdoc />
         public override void Post(SendOrPostCallback d, object? state)
         {
@@ -279,7 +273,6 @@ public sealed class DriverHostTests
             _queue.Enqueue(() => d(state));
         }
 
-        /// <summary>Sends a callback synchronously.</summary>
         /// <inheritdoc />
         public override void Send(SendOrPostCallback d, object? state)
         {