Use helper-style primitives in v2 test fixtures

The v2 authoring API supports two equivalent styles: namespaced helpers
(the primary API, `use function Workflow\V2\activity;`) and the static
facade (`Workflow::activity()`). Issue #171 calls for the helper style
to be the primary example throughout fixtures so that new authors reading
the test suite see it as the default.

Three fixtures used `Workflow::now()`, `Workflow::uuid4()`, `Workflow::uuid7()`,
and `Workflow::awaitSignal()` calls mixed with helper-style activity/all
calls. Switch those to the namespaced helpers `now()`, `uuid4()`, `uuid7()`,
and `await('<signal>')` so every fixture in the V2 suite reads in one
consistent style. The static facade delegates to the same helpers, so
behavior is identical.

Author: durable-workflow-ops

tests/Fixtures/V2/TestDeterministicTimeWorkflow.php

@@ -5,15 +5,17 @@
 namespace Tests\Fixtures\V2;
 
 use function Workflow\V2\activity;
+use function Workflow\V2\now;
+
 use Workflow\V2\Workflow;
 
 final class TestDeterministicTimeWorkflow extends Workflow
 {
     public function handle(string $name): array
     {
-        $timeAtStart = Workflow::now();
+        $timeAtStart = now();
         $greeting = activity(TestGreetingActivity::class, $name);
-        $timeAfterActivity = Workflow::now();
+        $timeAfterActivity = now();
 
         return [
             'greeting' => $greeting,

tests/Fixtures/V2/TestParallelDeterministicTimeWorkflow.php

@@ -6,20 +6,22 @@
 
 use function Workflow\V2\activity;
 use function Workflow\V2\all;
+use function Workflow\V2\now;
+
 use Workflow\V2\Workflow;
 
 final class TestParallelDeterministicTimeWorkflow extends Workflow
 {
     public function handle(string $firstName, string $secondName): array
     {
-        $timeAtStart = Workflow::now();
+        $timeAtStart = now();
 
         $results = all([
             static fn () => activity(TestGreetingActivity::class, $firstName),
             static fn () => activity(TestGreetingActivity::class, $secondName),
         ]);
 
-        $timeAfterParallel = Workflow::now();
+        $timeAfterParallel = now();
 
         return [
             'results' => $results,

tests/Fixtures/V2/TestUuidWorkflow.php

@@ -7,6 +7,10 @@
 use Workflow\QueryMethod;
 use Workflow\V2\Attributes\Signal;
 use Workflow\V2\Attributes\Type;
+
+use function Workflow\V2\await;
+use function Workflow\V2\uuid4;
+use function Workflow\V2\uuid7;
 use Workflow\V2\Workflow;
 
 #[Type('test-uuid-workflow')]
@@ -24,11 +28,11 @@ final class TestUuidWorkflow extends Workflow
     public function handle(): array
     {
         $this->ids = [
-            'uuid4' => [Workflow::uuid4(), Workflow::uuid4()],
-            'uuid7' => [Workflow::uuid7(), Workflow::uuid7()],
+            'uuid4' => [uuid4(), uuid4()],
+            'uuid7' => [uuid7(), uuid7()],
         ];
 
-        Workflow::awaitSignal('finish');
+        await('finish');
 
         return $this->ids;
     }