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/Resilience/FlakeyDriverIntegrationTests.cs

@@ -15,6 +15,7 @@ namespace ZB.MOM.WW.OtOpcUa.Core.Tests.Resilience;
 public sealed class FlakeyDriverIntegrationTests
 {
     /// <summary>Verifies read succeeds after transient failures with retries.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Read_SurfacesSuccess_AfterTransientFailures()
     {
@@ -43,6 +44,7 @@ public sealed class FlakeyDriverIntegrationTests
     }
 
     /// <summary>Verifies non-idempotent write fails on first failure without replay.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Write_NonIdempotent_FailsOnFirstFailure_NoReplay()
     {
@@ -68,6 +70,7 @@ public sealed class FlakeyDriverIntegrationTests
     }
 
     /// <summary>Verifies idempotent write retries until success.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Write_Idempotent_RetriesUntilSuccess()
     {
@@ -93,6 +96,7 @@ public sealed class FlakeyDriverIntegrationTests
     }
 
     /// <summary>Verifies multiple hosts have independent failure counts and circuit breakers.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task MultipleHosts_OnOneDriver_HaveIndependentFailureCounts()
     {
@@ -141,10 +145,7 @@ public sealed class FlakeyDriverIntegrationTests
             _failWritesBeforeIndex = failWritesBeforeIndex;
         }
 
-        /// <summary>Reads values, failing transiently until the threshold.</summary>
-        /// <param name="fullReferences">Full references to read.</param>
-        /// <param name="cancellationToken">Cancellation token.</param>
-        /// <returns>Data value snapshots.</returns>
+        /// <inheritdoc />
         public Task<IReadOnlyList<DataValueSnapshot>> ReadAsync(
             IReadOnlyList<string> fullReferences,
             CancellationToken cancellationToken)
@@ -160,10 +161,7 @@ public sealed class FlakeyDriverIntegrationTests
             return Task.FromResult(result);
         }
 
-        /// <summary>Writes values, failing transiently until the threshold.</summary>
-        /// <param name="writes">The write requests.</param>
-        /// <param name="cancellationToken">Cancellation token.</param>
-        /// <returns>Write results.</returns>
+        /// <inheritdoc />
         public Task<IReadOnlyList<WriteResult>> WriteAsync(
             IReadOnlyList<WriteRequest> writes,
             CancellationToken cancellationToken)