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.ConfigurationDatabase.Tests/MediumPersistenceRegressionTests.cs

@@ -18,6 +18,8 @@ public class MediumPersistenceRegressionTests
         return db;
     }
 
+    /// <summary>Verifies that an instance unique name cannot exist at two different sites.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
     [Fact]
     public async Task DL1_UniqueNameCannotExistAtTwoSites()
     {
@@ -28,6 +30,8 @@ public class MediumPersistenceRegressionTests
         await Assert.ThrowsAsync<InstanceNameConflictException>(() => db.SaveChangesAsync());
     }
 
+    /// <summary>Verifies that a context with a different data protection key cannot read protected connection configuration.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
     [Fact]
     public async Task DL2_ConvertersDoNotShareKeysAcrossProviders()
     {
@@ -45,6 +49,8 @@ public class MediumPersistenceRegressionTests
             wrongKey.DataConnections.SingleAsync(c => c.Name == "key-isolation"));
     }
 
+    /// <summary>Verifies that the legacy upgrade protects both configuration columns and is safe to run twice.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
     [Fact]
     public async Task DL2_LegacyUpgradeProtectsBothColumnsAndIsIdempotent()
     {
@@ -63,6 +69,9 @@ public class MediumPersistenceRegressionTests
         Assert.Contains("backup-secret", row.BackupConfiguration);
     }
 
+    /// <summary>Verifies that data connection configuration is stored encrypted and reads back unchanged.</summary>
+    /// <param name="backup">True to exercise the backup configuration column, false for the primary.</param>
+    /// <returns>A task that represents the asynchronous operation.</returns>
     [Theory]
     [InlineData(false)]
     [InlineData(true)]
@@ -83,6 +92,9 @@ public class MediumPersistenceRegressionTests
         Assert.Equal(secret, backup ? loaded.BackupConfiguration : loaded.PrimaryConfiguration);
     }
 
+    /// <summary>Verifies that a context without a data protection provider refuses to write connection configuration.</summary>
+    /// <param name="backup">True to exercise the backup configuration column, false for the primary.</param>
+    /// <returns>A task that represents the asynchronous operation.</returns>
     [Theory]
     [InlineData(false)]
     [InlineData(true)]