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.CLI.Tests/CredentialResolutionTests.cs

@@ -3,7 +3,7 @@ using ZB.MOM.WW.ScadaBridge.CLI;
 namespace ZB.MOM.WW.ScadaBridge.CLI.Tests;
 
 /// <summary>
-/// Regression tests for CLI-006 — credentials could only be supplied via the
+/// Regression tests for environment-based credential supply — credentials could only be supplied via the
 /// <c>--password</c> command-line option, which leaks into process listings and
 /// shell history. A <c>SCADABRIDGE_PASSWORD</c> / <c>SCADABRIDGE_USERNAME</c> environment
 /// fallback gives CI/CD a safer alternative.
@@ -11,6 +11,7 @@ namespace ZB.MOM.WW.ScadaBridge.CLI.Tests;
 [Collection("Environment")]
 public class CredentialResolutionTests
 {
+    /// <summary>Verifies that the password is loaded from the environment variable.</summary>
     [Fact]
     public void Load_Password_FromEnvironment()
     {
@@ -29,6 +30,7 @@ public class CredentialResolutionTests
         }
     }
 
+    /// <summary>Verifies that the username is loaded from the environment variable.</summary>
     [Fact]
     public void Load_Username_FromEnvironment()
     {
@@ -47,6 +49,7 @@ public class CredentialResolutionTests
         }
     }
 
+    /// <summary>Verifies that loading with no credential environment variables leaves the credentials null.</summary>
     [Fact]
     public void Load_NoCredentialEnvVars_LeavesCredentialsNull()
     {