docs(tests): fix CommentChecker findings across tests/ — 13,392 → 0 (repo-wide scan clean)

Comment/XML-doc changes only:
- add summaries to ~10k test methods, fixtures, fakes and helpers
  (+ <param> on theories, <returns> on async Task methods,
  <inheritdoc/> on interface implementations the checker can resolve)
- strip ~2.6k project-tracking references (WP*, P*-*, row-NN, Task N,
  #NN, Component-0NN) from comments, keeping the explanatory text;
  reword false positives in comments only
- real docs on fakes implementing BCL/library interfaces
  (IDisposable, ILogger, IOptionsMonitor, IAsyncLifetime)
- reword the last 5 src/ false positives (CWE-1236, failures-1,
  year-0001, M365)

Only non-comment edits: four one-line nested classes split across lines
so members can carry docs. Build 0 errors / 0 warnings.

tests/ZB.MOM.WW.ScadaBridge.AuditLog.Tests/Central/CentralAuditRedactionFailureCounterTests.cs

@@ -11,16 +11,17 @@ using ZB.MOM.WW.ScadaBridge.AuditLog.Payload;
 namespace ZB.MOM.WW.ScadaBridge.AuditLog.Tests.Central;
 
 /// <summary>
-/// Bundle E (M6-T9) coverage for the central-side payload-filter redactor
-/// failure bridge. M5 wired the SITE bridge
+/// Coverage for the central-side payload-filter redactor
+/// failure bridge. The SITE bridge
 /// (<c>HealthMetricsAuditRedactionFailureCounter</c>) that pushes increments
-/// into the site health report; M6 mirrors that with
+/// into the site health report; the central bridge mirrors that with
 /// <see cref="CentralAuditRedactionFailureCounter"/> so the same payload
 /// filter — when it runs on the central writer paths — surfaces failures on
 /// the central <see cref="AuditCentralHealthSnapshot"/>.
 /// </summary>
 public class CentralAuditRedactionFailureCounterTests : TestKit
 {
+    /// <summary>Verifies that incrementing the counter routes the failure to the central health snapshot.</summary>
     [Fact]
     public void Increment_Routes_To_Snapshot()
     {
@@ -34,6 +35,7 @@ public class CentralAuditRedactionFailureCounterTests : TestKit
         Assert.Equal(3, snapshot.AuditRedactionFailure);
     }
 
+    /// <summary>Verifies that constructing the counter with a null snapshot throws.</summary>
     [Fact]
     public void Construction_With_Null_Snapshot_Throws()
     {
@@ -41,6 +43,7 @@ public class CentralAuditRedactionFailureCounterTests : TestKit
             () => new CentralAuditRedactionFailureCounter(null!));
     }
 
+    /// <summary>Verifies that registering central maintenance replaces the redaction failure counter with the central implementation.</summary>
     [Fact]
     public void AddAuditLogCentralMaintenance_Replaces_IAuditRedactionFailureCounter_With_CentralImpl()
     {
@@ -72,11 +75,12 @@ public class CentralAuditRedactionFailureCounterTests : TestKit
         Assert.IsType<CentralAuditRedactionFailureCounter>(counter);
     }
 
+    /// <summary>Verifies that the default redaction failure counter registered by the audit log is a no-op.</summary>
     [Fact]
     public void AddAuditLog_Default_IAuditRedactionFailureCounter_Is_NoOp()
     {
         // Sanity check: without AddAuditLogCentralMaintenance the default
-        // remains the NoOp from M5 — the central bridge only takes effect
+        // remains the NoOp — the central bridge only takes effect
         // when the central-only registration runs.
         var config = new ConfigurationBuilder()
             .AddInMemoryCollection(new Dictionary<string, string?>