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>

config/sync/block.block.olivero_site_branding.yml

@@ -0,0 +1,25 @@
+uuid: 28f53ba3-ed0a-4978-b48b-a18a69d74655
+langcode: en
+status: true
+dependencies:
+  module:
+    - system
+  theme:
+    - olivero
+_core:
+  default_config_hash: '-OAAZDw1OR_UyAEPEKX0Hu4LaZD149vW9PmMnIC-v0o'
+id: olivero_site_branding
+theme: olivero
+region: header
+weight: 0
+provider: null
+plugin: system_branding_block
+settings:
+  id: system_branding_block
+  label: 'Site branding'
+  label_display: '0'
+  provider: system
+  use_site_logo: true
+  use_site_name: true
+  use_site_slogan: true
+visibility: {  }