Tidy automation backend: run duration, folded migrations, imports

- Add AutomationRun::durationInMilliseconds() as the single source of truth
  for the Invocations list and metrics, replacing the duplicated inline diff.
- Fold the variables and root_run_id columns into their create migrations
  (this branch isn't in production) and drop the standalone alters.
- Import Illuminate\Http\Response (aliased) instead of referencing it inline.

app/Actions/Automation/Automation/GetAutomationMetrics.php

@@ -43,8 +43,8 @@ public function __invoke(Automation $automation, CarbonInterface $start, CarbonI
         $successRate = $finished > 0 ? (int) round($completed->count() / $finished * 100) : null;
 
         $durations = $completed
-            ->filter(fn ($run) => $run->started_at !== null && $run->finished_at !== null)
-            ->map(fn ($run) => $run->started_at->diffInMilliseconds($run->finished_at));
+            ->map(fn ($run) => $run->durationInMilliseconds())
+            ->filter(fn ($ms) => $ms !== null);
         $avgDurationMs = $durations->isNotEmpty() ? (int) round($durations->avg()) : null;
 
         return [

app/Http/Controllers/App/AutomationController.php

@@ -33,6 +33,7 @@
 use App\Models\AutomationRun;
 use Illuminate\Http\JsonResponse;
 use Illuminate\Http\RedirectResponse;
+use Illuminate\Http\Response as HttpResponse;
 use Inertia\Inertia;
 use Inertia\Response;
 
@@ -183,7 +184,7 @@ public function retryRun(
         RetryRunFromNode $retry,
         Automation $automation,
         AutomationRun $run,
-    ): \Illuminate\Http\Response {
+    ): HttpResponse {
         $this->authorize('update', $automation);
         abort_unless($run->automation_id === $automation->id, 404);
 

app/Http/Resources/AutomationInvocationResource.php

@@ -18,16 +18,12 @@ class AutomationInvocationResource extends JsonResource
      */
     public function toArray(Request $request): array
     {
-        $durationMs = $this->started_at !== null && $this->finished_at !== null
-            ? $this->started_at->diffInMilliseconds($this->finished_at)
-            : null;
-
         return [
             'id' => $this->id,
             'status' => $this->status->value,
             'is_manual' => (bool) $this->is_manual,
             'node_run_count' => (int) ($this->node_runs_count ?? 0),
-            'duration_ms' => $durationMs,
+            'duration_ms' => $this->durationInMilliseconds(),
             'error_message' => is_array($this->error) ? ($this->error['message'] ?? null) : $this->error,
             'created_at' => $this->created_at,
             'started_at' => $this->started_at,

app/Models/AutomationRun.php

@@ -48,6 +48,19 @@ public function rootId(): string
         return $this->root_run_id ?? $this->id;
     }
 
+    /**
+     * Wall-clock execution time, or null while the run hasn't both started and
+     * finished. Single source of truth for the Invocations list and metrics.
+     */
+    public function durationInMilliseconds(): ?int
+    {
+        if ($this->started_at === null || $this->finished_at === null) {
+            return null;
+        }
+
+        return (int) $this->started_at->diffInMilliseconds($this->finished_at);
+    }
+
     /**
      * Context for template (`{{ ... }}`) resolution: the run context plus the
      * automation's workflow variables, merged in-memory. Variables are NEVER

database/migrations/2026_05_22_211640_create_automations_table.php

@@ -22,6 +22,7 @@ public function up(): void
             $table->string('trigger_type')->nullable();
             $table->json('nodes')->nullable();
             $table->json('connections')->nullable();
+            $table->json('variables')->nullable();
             $table->timestamp('activated_at')->nullable();
             $table->timestamp('paused_at')->nullable();
             $table->timestamps();

database/migrations/2026_05_22_211642_create_automation_runs_table.php

@@ -16,6 +16,7 @@ public function up(): void
         Schema::create('automation_runs', function (Blueprint $table) {
             $table->uuid('id')->primary();
             $table->foreignUuid('automation_id')->constrained('automations')->cascadeOnDelete();
+            $table->foreignUuid('root_run_id')->nullable();
             $table->foreignUuid('trigger_item_id')->nullable()->constrained('automation_trigger_items')->nullOnDelete();
             $table->string('current_node_id')->nullable();
             $table->string('status')->default('pending');
@@ -32,6 +33,10 @@ public function up(): void
             $table->index(['automation_id', 'status']);
             $table->index(['status', 'next_action_at']);
         });
+
+        Schema::table('automation_runs', function (Blueprint $table) {
+            $table->foreign('root_run_id')->references('id')->on('automation_runs')->nullOnDelete();
+        });
     }
 
     /**

database/migrations/2026_06_11_181832_add_variables_to_automations_table.php

@@ -1,28 +0,0 @@
-<?php
-
-use Illuminate\Database\Migrations\Migration;
-use Illuminate\Database\Schema\Blueprint;
-use Illuminate\Support\Facades\Schema;
-
-return new class extends Migration
-{
-    /**
-     * Run the migrations.
-     */
-    public function up(): void
-    {
-        Schema::table('automations', function (Blueprint $table) {
-            $table->json('variables')->nullable()->after('connections');
-        });
-    }
-
-    /**
-     * Reverse the migrations.
-     */
-    public function down(): void
-    {
-        Schema::table('automations', function (Blueprint $table) {
-            $table->dropColumn('variables');
-        });
-    }
-};

database/migrations/2026_06_11_213339_add_root_run_id_to_automation_runs_table.php

@@ -1,28 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-use Illuminate\Database\Migrations\Migration;
-use Illuminate\Database\Schema\Blueprint;
-use Illuminate\Support\Facades\Schema;
-
-return new class extends Migration
-{
-    public function up(): void
-    {
-        Schema::table('automation_runs', function (Blueprint $table) {
-            // Links every run forked by a fan-out back to the run that started the
-            // execution, so the editor test panel can aggregate all branches of a
-            // single test under one root. Null on the root run itself.
-            $table->foreignUuid('root_run_id')->nullable()->after('automation_id')
-                ->constrained('automation_runs')->nullOnDelete();
-        });
-    }
-
-    public function down(): void
-    {
-        Schema::table('automation_runs', function (Blueprint $table) {
-            $table->dropConstrainedForeignId('root_run_id');
-        });
-    }
-};

tests/Feature/Automation/AutomationModelTest.php

@@ -38,6 +38,19 @@
     expect($automation->trigger_type)->toBeNull();
 });
 
+it('computes run duration only once both timestamps are set', function () {
+    $start = now()->startOfSecond();
+
+    $running = AutomationRun::factory()->make(['started_at' => $start, 'finished_at' => null]);
+    $finished = AutomationRun::factory()->make([
+        'started_at' => $start,
+        'finished_at' => $start->copy()->addSeconds(2),
+    ]);
+
+    expect($running->durationInMilliseconds())->toBeNull()
+        ->and($finished->durationInMilliseconds())->toBe(2000);
+});
+
 it('relates trigger items, runs and node runs', function () {
     $automation = Automation::factory()->create();
     $item = AutomationTriggerItem::factory()->for($automation)->create();