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.

src/ZB.MOM.WW.ScadaBridge.HealthMonitoring/SiteHealthState.cs

@@ -26,7 +26,7 @@ public sealed record SiteHealthState
     /// <c>null</c> if the site is known only via heartbeats and has not yet sent
     /// a report. Used by the UI to surface report staleness during failover;
     /// the <c>null</c> case must be rendered as "no report yet" rather than as a
-    /// timestamp (a <c>default</c> sentinel would display as year-0001).
+    /// timestamp (a <c>default</c> sentinel would display as year 0001).
     /// </summary>
     public DateTimeOffset? LastReportReceivedAt { get; init; }