test(coverage): close Theme 8 — 13 test-coverage findings, +35 tests

13 well-bounded test-coverage gaps closed across 11 test projects.
Net +35 regression tests; no production code changes except the
SiteEventLogger src reference unchanged (W3 redacted only test code).

Test additions:
- CLI-022: CommandTreeTests pinned-count assertion bumped 14→16 and
  3 InlineData rows added for the audit + bundle command groups.
- Commons-020: new TransportRecordsTests covers BundleManifest /
  ExportSelection / ImportPreview / ImportResolution / ImportResult —
  ctor + System.Text.Json round-trip + record-equality (14 tests).
- CD-024: SPLIT-RANGE failure-continuation now under
  EnsureLookahead_SecondSplitThrows_LoopAborts_FirstBoundaryStillCommitted
  (Skippable MS-SQL fixture); production-shape rowversion delete
  asserted by DeleteDeploymentRecord_CurrentRowVersion_StubAttachPath_DeleteSucceeds.
- CentralUI-033: new QueryStringDrillInTests with 4 bUnit cases for
  Transport + SiteCalls drill-in / query-string handling.
- DM-024: probe actors (ReconcileProbeActor, SerializationProbeActor,
  ArtifactProbeActor) refactored from static fields to per-test instances
  (Interlocked on counter) — all 31 callers updated; no production
  changes required.
- HM-022: real-time PeriodicTimer test flake fixed by replacing
  fixed-budget Task.Delay with a RunLoopUntil poll-until-condition
  helper (5s/25ms). Production loop untouched.
- InboundAPI-023: new EndpointExtensionsTests covers the
  POST /api/{methodName} composition wiring via TestServer (7 cases:
  happy path, missing key 401, unknown method 403, invalid JSON 400,
  missing param 400, script-throws 500 sanitised, AuditActorItemKey
  stash invariant).
- MgmtSvc-021: 6 new ManagementActorTests cover the Transport bundle
  handlers (role gate for Export/Preview/Import, unknown-name
  ManagementCommandException, blocker-rejection, dedupe last-write-wins).
- SCA-006: SiteCallQueryRequest_StuckOnly_CursorAtNonStuckBoundary_SkipsToNextStuckRow
  pins the missing boundary case.
- SEL-023: stress-test `bool stop` promoted to `volatile bool` for
  cross-thread visibility under release/JIT.

Verify-only resolutions:
- NS-024: closed by NS-019 (commit ac96b83 deletion of
  NotificationDeliveryService + its test file). No edits needed.
- NotifOutbox-008: FallbackMaxRetries/FallbackRetryDelay are private
  forward-compat constants returned only when no SMTP-config row exists
  (in which case EmailNotificationDeliveryAdapter returns Permanent,
  bypassing the values entirely). Marked Resolved with note.
- Transport-010: Overwrite child-collection sync covered by the T-001/
  T-002 tests added in commit e3ca9af; per-IP throttle by
  BundleUnlockRateLimiterTests; failed-session retention by
  BundleSessionStoreTests; T-009 closed structurally via AsyncLocal.
  Marked Resolved by reference.

Build clean; all 11 affected test suites green. README regenerated:
33 open (was 46).

tests/ScadaLink.ConfigurationDatabase.Tests/RepositoryCoverageTests.cs

@@ -847,6 +847,44 @@ public class DeploymentManagerRepositoryTests : IDisposable
         Assert.Null(await _repository.GetDeploymentRecordByIdAsync(id));
     }
 
+    /// <summary>
+    /// ConfigurationDatabase-024: CD-017 added optimistic-concurrency to
+    /// <c>DeleteDeploymentRecordAsync(int id, byte[] expectedRowVersion)</c> — the stub-attach
+    /// path now seeds <c>OriginalValues["RowVersion"]</c> from the caller's last-observed
+    /// value so the generated SQL becomes <c>DELETE … WHERE Id = @id AND RowVersion = @prior</c>.
+    /// This test pins the production-shape happy path: caller holds the entity's CURRENT
+    /// RowVersion, clears the change-tracker (i.e. no tracked instance — exactly the M&amp;V
+    /// admin / handler shape), calls Delete with that token, and the delete completes
+    /// without throwing <see cref="Microsoft.EntityFrameworkCore.DbUpdateConcurrencyException"/>.
+    /// </summary>
+    [Fact]
+    public async Task DeleteDeploymentRecord_CurrentRowVersion_StubAttachPath_DeleteSucceeds()
+    {
+        // STM: CD-024-RowVersionDeleteHappyPath marker.
+        var instance = await SeedInstanceAsync();
+        var record = new DeploymentRecord("d-rv-001", "admin")
+        {
+            InstanceId = instance.Id,
+            DeployedAt = DateTimeOffset.UtcNow,
+        };
+        await _repository.AddDeploymentRecordAsync(record);
+        await _repository.SaveChangesAsync();
+
+        // Capture the entity's CURRENT RowVersion (the one the caller would have
+        // read from a prior GetDeploymentRecordByIdAsync), then detach so the
+        // delete travels through the stub-attach branch (no tracked entity).
+        var id = record.Id;
+        var currentRowVersion = record.RowVersion ?? Array.Empty<byte>();
+        _context.ChangeTracker.Clear();
+
+        // No NotSupported/Concurrency exception should fire on this code path.
+        await _repository.DeleteDeploymentRecordAsync(id, currentRowVersion);
+        var affected = await _repository.SaveChangesAsync();
+
+        Assert.Equal(1, affected);
+        Assert.Null(await _repository.GetDeploymentRecordByIdAsync(id));
+    }
+
     [Fact]
     public async Task DeleteInstance_RemovesRestrictFkDeploymentRecordsFirst()
     {