Use JSON-key-order-agnostic assertions + waitFor child on status drift tests

MySQL 8 JSON columns sort keys by (length, alpha), which doesn't match
the literal-array order tests wrote. Swap three remaining
assertSame([...], $json_column) comparisons over to assertSameJsonObject
so they round-trip identically on MySQL and SQLite — matching the
pattern in 414843a / b81a943 / 26c587b.

Also: testWorkflowSummaryProjectsChildWaitAndHealthyRepairNoOp loaded
the child run before the child workflow task had executed, which left
it in the RunStatus::Pending bucket — then the test asserted 'waiting'.
The intent is to observe the child in its parked-for-timer state, so
add a waitFor on the child's RunStatus transitioning to Waiting before
sampling.

Clears 3 MySQL failures under #399:
  * testStartRecordsBusinessKeyAndLabels
  * testWorkflowCanContinueAsNewAcrossRuns
  * testWorkflowSummaryProjectsChildWaitAndHealthyRepairNoOp
  * testNestedParallelActivityAllWaitsForOuterActivityBeforeResumingParent…
  * testWorkflowCanWaitForChildWorkflowAndCompleteWithChildOutput

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: durable-workflow-ops

tests/Feature/V2/V2WorkflowControlPlaneTest.php

@@ -345,11 +345,11 @@ public function testStartRecordsBusinessKeyAndLabels(): void
 
         $run = WorkflowRun::query()->find($result['workflow_run_id']);
         $this->assertSame('order-12345', $run->business_key);
-        $this->assertSame([
+        $this->assertSameJsonObject([
             'team' => 'payments',
             'env' => 'staging',
         ], $run->visibility_labels);
-        $this->assertSame([
+        $this->assertSameJsonObject([
             'description' => 'Test workflow',
         ], $run->memo);
     }

tests/Feature/V2/V2WorkflowTest.php

@@ -2717,7 +2717,7 @@ public function testWorkflowCanContinueAsNewAcrossRuns(): void
 
         $this->assertSame('workflow', $secondRunStart->source);
         $this->assertSame('Workflow', $secondRunStart->callerLabel());
-        $this->assertSame([
+        $this->assertSameJsonObject([
             'parent_instance_id' => 'continue-instance',
             'parent_run_id' => $runs[0]->id,
             'sequence' => 2,
@@ -2726,7 +2726,7 @@ public function testWorkflowCanContinueAsNewAcrossRuns(): void
 
         $this->assertSame('workflow', $thirdRunStart->source);
         $this->assertSame('Workflow', $thirdRunStart->callerLabel());
-        $this->assertSame([
+        $this->assertSameJsonObject([
             'parent_instance_id' => 'continue-instance',
             'parent_run_id' => $runs[1]->id,
             'sequence' => 2,
@@ -2858,7 +2858,7 @@ public function testWorkflowCanWaitForChildWorkflowAndCompleteWithChildOutput():
 
         $this->assertSame('workflow', $childStart->source);
         $this->assertSame('Workflow', $childStart->callerLabel());
-        $this->assertSame([
+        $this->assertSameJsonObject([
             'parent_instance_id' => 'parent-child-instance',
             'parent_run_id' => $parentRunId,
             'sequence' => 1,
@@ -2909,8 +2909,13 @@ public function testWorkflowSummaryProjectsChildWaitAndHealthyRepairNoOp(): void
             ->where('link_type', 'child_workflow')
             ->sole();
 
+        $childRunId = $link->child_workflow_run_id;
+        $this->waitFor(
+            static fn (): bool => WorkflowRun::query()->findOrFail($childRunId)->status === RunStatus::Waiting
+        );
+
         /** @var WorkflowRun $childRun */
-        $childRun = WorkflowRun::query()->findOrFail($link->child_workflow_run_id);
+        $childRun = WorkflowRun::query()->findOrFail($childRunId);
         $summary = $workflow->summary();
 
         $this->assertSame('waiting', $workflow->status());
@@ -3537,7 +3542,7 @@ public function testNestedParallelActivityAllWaitsForOuterActivityBeforeResuming
             ->sole(static fn (WorkflowHistoryEvent $event): bool => ($event->payload['sequence'] ?? null) === 3);
 
         $this->assertSame('parallel-activities:1:3', $firstActivityScheduled->payload['parallel_group_id'] ?? null);
-        $this->assertSame([
+        $this->assertSameJsonObject([
             [
                 'parallel_group_id' => 'parallel-activities:1:3',
                 'parallel_group_kind' => 'activity',
@@ -3548,7 +3553,7 @@ public function testNestedParallelActivityAllWaitsForOuterActivityBeforeResuming
         ], $firstActivityScheduled->payload['parallel_group_path'] ?? null);
 
         $this->assertSame('parallel-activities:2:2', $secondActivityScheduled->payload['parallel_group_id'] ?? null);
-        $this->assertSame([
+        $this->assertSameJsonObject([
             [
                 'parallel_group_id' => 'parallel-activities:1:3',
                 'parallel_group_kind' => 'activity',
@@ -3566,7 +3571,7 @@ public function testNestedParallelActivityAllWaitsForOuterActivityBeforeResuming
         ], $secondActivityScheduled->payload['parallel_group_path'] ?? null);
 
         $this->assertSame('parallel-activities:2:2', $thirdActivityScheduled->payload['parallel_group_id'] ?? null);
-        $this->assertSame([
+        $this->assertSameJsonObject([
             [
                 'parallel_group_id' => 'parallel-activities:1:3',
                 'parallel_group_kind' => 'activity',