Initial Drupal site: content model + validation + Vue dashboard

- Content type "Ligne comptable" with Paragraphs "Répartition" (Compte + Montant)
- Taxonomies: Compte (9 comptes) and Client (unified client list)
- hook_node_presave + form validate: sum(répartition) must equal montant HT
- /dashboard route (progressive decoupling): Vue 3 app fetching JSON:API,
  computing solde par compte / par client client-side
- "Ajouter une ligne" opens the real Drupal node form in an AJAX modal
- Gin as default + admin theme
- 9 opening-balance lines seeded from suivi_compta_SASFigli2026_v2.ods

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

web/autoload_runtime.php

@@ -0,0 +1,22 @@
+<?php
+
+/**
+ * @file
+ * Includes the autoload_runtime created by the Symfony Runtime component.
+ *
+ * This file was generated by drupal-scaffold.
+ *
+ * @see composer.json
+ * @see index.php
+ * @see core/install.php
+ * @see core/rebuild.php
+ */
+
+use Drupal\Core\Runtime\DrupalRuntime;
+
+// By default, the symfony/runtime component would load SymfonyRuntime as its
+// runtime. However, Drupal's Kernel has a lot of runtime components that it
+// expects to be prepared. Thus, we default Drupal applications to DrupalRuntime
+// instead to make this easily accessible.
+$_ENV['APP_RUNTIME'] ??= $_SERVER['APP_RUNTIME'] ?? DrupalRuntime::class;
+return require __DIR__ . '/../vendor/autoload_runtime.php';