feat(project-service): wire SupplierSnapshotGuard into delete() and update()

app/app/Services/Project/ProjectService.php

@@ -18,6 +18,7 @@ class ProjectService
 {
     public function __construct(
         private readonly OperationsLogger $ops = new OperationsLogger,
+        private readonly SupplierSnapshotGuard $snapshotGuard = new SupplierSnapshotGuard,
     ) {}
 
     public function update(Project $project, array $data): Project
@@ -30,6 +31,15 @@ class ProjectService
             $data['supplier_b1_project_id'], $data['supplier_b2_project_id'], $data['supplier_b3_project_id'],
         );
 
+        // Spec: docs/superpowers/plans/2026-05-26-supplier-snapshot-guard.md
+        // Если меняем источник (signal_identifier / sms_senders / sms_keyword) — guard.
+        $sourceFieldsTouched = array_key_exists('signal_identifier', $data)
+            || array_key_exists('sms_senders', $data)
+            || array_key_exists('sms_keyword', $data);
+        if ($sourceFieldsTouched) {
+            $this->snapshotGuard->assertCanMutateSource($project, 'change_source');
+        }
+
         if (isset($data['daily_limit_target']) && $data['daily_limit_target'] < $project->delivered_today) {
             throw new HttpResponseException(response()->json([
                 'errors' => [
@@ -149,6 +159,11 @@ class ProjectService
 
     public function delete(Project $project): void
     {
+        // Spec: docs/superpowers/plans/2026-05-26-supplier-snapshot-guard.md
+        // Guard поставщикова слепка ПЕРЕД has-deals (приоритетней) — клиент должен
+        // увидеть формулировку про «уже заказали лиды», а не «есть сделки».
+        $this->snapshotGuard->assertCanMutateSource($project, 'delete');
+
         $hasDeals = DB::table('deals')->where('project_id', $project->id)->exists();
         if ($hasDeals) {
             throw new HttpResponseException(response()->json([