feat(applications): add configurable stop grace period

Add centralized stop grace period resolution for application settings and use it across manual stops, preview stops, and deployments. Validate the Livewire advanced setting against shared min/max constants and cover persistence, fillable creation, and fallback behavior with tests.

app/Livewire/Project/Application/Advanced.php

@@ -4,6 +4,8 @@ namespace App\Livewire\Project\Application;
 
 use App\Models\Application;
 use Illuminate\Foundation\Auth\Access\AuthorizesRequests;
+use Illuminate\Support\Facades\Validator;
+use Illuminate\Validation\ValidationException;
 use Livewire\Attributes\Validate;
 use Livewire\Component;
 
@@ -264,24 +266,21 @@ class Advanced extends Component
         try {
             $this->authorize('update', $this->application);
 
-            // Convert empty string to null, otherwise cast to integer
-            $value = ($this->stopGracePeriod === '' || $this->stopGracePeriod === null)
+            $validated = Validator::make(
+                ['stopGracePeriod' => $this->stopGracePeriod === '' ? null : $this->stopGracePeriod],
+                ['stopGracePeriod' => ['nullable', 'integer', 'min:'.MIN_STOP_GRACE_PERIOD_SECONDS, 'max:'.MAX_STOP_GRACE_PERIOD_SECONDS]],
+                [],
+                ['stopGracePeriod' => 'stop grace period']
+            )->validate();
+
+            $this->application->settings->stop_grace_period = $validated['stopGracePeriod'] === null
                 ? null
-                : (int) $this->stopGracePeriod;
-
-            // Validate the integer value
-            if ($value !== null && ($value < 1 || $value > 3600)) {
-                $this->dispatch('error', 'Stop grace period must be between 1 and 3600 seconds.');
-
-                return;
-            }
-
-            // Save to model
-            $this->application->settings->stop_grace_period = $value;
+                : (int) $validated['stopGracePeriod'];
             $this->application->settings->save();
 
-            // User feedback
             $this->dispatch('success', 'Stop grace period updated.');
+        } catch (ValidationException $e) {
+            throw $e;
         } catch (\Throwable $e) {
             return handleError($e, $this);
         }