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/CapabilityInvokerTests.cs

@@ -14,6 +14,7 @@ public sealed class CapabilityInvokerTests
         new(builder, "drv-test", () => options);
 
     /// <summary>Verifies that the capability invoker returns the value from the call site.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Read_ReturnsValue_FromCallSite()
     {
@@ -29,6 +30,7 @@ public sealed class CapabilityInvokerTests
     }
 
     /// <summary>Verifies that the capability invoker retries on transient failures.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Read_Retries_OnTransientFailure()
     {
@@ -52,6 +54,7 @@ public sealed class CapabilityInvokerTests
     }
 
     /// <summary>Verifies that non-idempotent writes do not retry even when the policy has retries configured.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Write_NonIdempotent_DoesNotRetry_EvenWhenPolicyHasRetries()
     {
@@ -85,6 +88,7 @@ public sealed class CapabilityInvokerTests
     }
 
     /// <summary>Verifies that idempotent writes retry when the policy has retries configured.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Write_Idempotent_Retries_WhenPolicyHasRetries()
     {
@@ -116,6 +120,7 @@ public sealed class CapabilityInvokerTests
     }
 
     /// <summary>Verifies that writes do not retry when the policy has zero retries configured.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Write_Default_DoesNotRetry_WhenPolicyHasZeroRetries()
     {
@@ -143,6 +148,7 @@ public sealed class CapabilityInvokerTests
     }
 
     /// <summary>Verifies that different hosts are honored independently in the resilience pipeline.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Execute_HonorsDifferentHosts_Independently()
     {
@@ -161,6 +167,7 @@ public sealed class CapabilityInvokerTests
     ///     redundant options objects on the per-write hot path and creates a consistency hazard
     ///     where an Admin edit mid-call could observe two different snapshots.
     /// </summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task ExecuteWriteAsync_NonIdempotent_Snapshots_Options_Once_Per_Call()
     {
@@ -195,6 +202,7 @@ public sealed class CapabilityInvokerTests
     ///     two derived values (<c>with</c> base + <c>Resolve(Write)</c>) come from the same options
     ///     instance.
     /// </summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task ExecuteWriteAsync_NonIdempotent_Uses_Consistent_Options_Snapshot()
     {