fix(multi-server): make applications on several servers consistent

- Stop the application on every server, also when one server is not functional.
- Write file mounts on every server of the application, not only on the main server.
- Deploy the exact commit, rollback flag and image tag of the main deployment to the
  additional servers, so a rollback reverts all servers.
- Pull the pushed image on additional servers for inline Dockerfile applications
  instead of building it again on each server.
- Fail multi-server deployments without a Docker image name, also from webhooks and the API.
- Send one deployment notification after all servers finish (parent_deployment_uuid).
- Block persistent volumes on multi-server applications (API, Livewire, SQLite connect)
  and warn in the deployment log for existing applications that have both.
- Remove dead code in push_to_docker_registry().

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

app/Models/ApplicationDeploymentQueue.php

@@ -39,6 +39,7 @@ use OpenApi\Attributes as OA;
         'deployment_url' => ['type' => 'string'],
         'destination_id' => ['type' => 'string'],
         'only_this_server' => ['type' => 'boolean'],
+        'parent_deployment_uuid' => ['type' => 'string', 'nullable' => true],
         'rollback' => ['type' => 'boolean'],
         'commit_message' => ['type' => 'string'],
     ],
@@ -105,6 +106,7 @@ class ApplicationDeploymentQueue extends Model
         'deployment_url',
         'destination_id',
         'only_this_server',
+        'parent_deployment_uuid',
         'rollback',
         'commit_message',
         'is_api',