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/Drivers/ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.Tests/AbLegacyRuntimeConcurrencyTests.cs

@@ -30,9 +30,7 @@ public sealed class AbLegacyRuntimeConcurrencyTests
         /// <param name="p">The tag creation parameters.</param>
         public OverlapDetectingFake(AbLegacyTagCreateParams p) : base(p) { }
 
-        /// <summary>Reads the tag asynchronously while tracking concurrent operations.</summary>
-        /// <param name="ct">The cancellation token.</param>
-        /// <returns>A task representing the read operation.</returns>
+        /// <inheritdoc />
         public override async Task ReadAsync(CancellationToken ct)
         {
             EnterOp();
@@ -45,9 +43,7 @@ public sealed class AbLegacyRuntimeConcurrencyTests
             finally { LeaveOp(); }
         }
 
-        /// <summary>Writes to the tag asynchronously while tracking concurrent operations.</summary>
-        /// <param name="ct">The cancellation token.</param>
-        /// <returns>A task representing the write operation.</returns>
+        /// <inheritdoc />
         public override async Task WriteAsync(CancellationToken ct)
         {
             EnterOp();
@@ -69,6 +65,7 @@ public sealed class AbLegacyRuntimeConcurrencyTests
     }
 
     /// <summary>Verifies that concurrent reads of the same tag are serialised against the shared runtime.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
     [Fact]
     public async Task Concurrent_reads_of_same_tag_are_serialised_against_the_shared_runtime()
     {
@@ -102,6 +99,7 @@ public sealed class AbLegacyRuntimeConcurrencyTests
     }
 
     /// <summary>Verifies that concurrent read and write operations on the same tag do not overlap.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
     [Fact]
     public async Task Concurrent_read_and_write_of_same_tag_do_not_overlap()
     {