feat(absences) : avancement module absences + suppression du portail client

Deux lots regroupés sur la branche feat/absence-management.

Suppression complète du portail client :
- retire ROLE_CLIENT (security.yaml) ; User::getRoles() ajoute toujours ROLE_USER
- supprime l'entité ClientTicket (+ repo, states, relations), User.client et
  User.allowedProjects, NotificationService, ProjectAllowedExtension, le bloc
  ROLE_CLIENT de MailAccessChecker
- front : pages /portal, layout portal, composants client-ticket/,
  AdminClientTicketTab, services/dto/i18n/docs associés
- fixtures : retire les users client-liot / client-acme
- migration Version20260522110000 (drop client_ticket, user_allowed_projects,
  colonnes liées ; task_document.task_id -> NOT NULL)
- tests : retire les cas obsolètes testant le blocage des clients sur le mail

Module gestion des absences (WIP) :
- entités / migrations (Version20260521160000, Version20260522090000)
- pages absences.vue / team-absences.vue, composants frontend/components/absence/
- services front, AccrueLeaveCommand, PublicHolidayController

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/package-lock.json

@@ -7,7 +7,7 @@
             "name": "nuxt-app",
             "hasInstallScript": true,
             "dependencies": {
-                "@malio/layer-ui": "^1.4.8",
+                "@malio/layer-ui": "^1.6.0",
                 "@nuxt/icon": "^2.2.1",
                 "@nuxtjs/i18n": "^10.2.3",
                 "@nuxtjs/tailwindcss": "^6.14.0",
@@ -2210,9 +2210,9 @@
             "license": "MIT"
         },
         "node_modules/@malio/layer-ui": {
-            "version": "1.4.8",
-            "resolved": "https://gitea.malio.fr/api/packages/MALIO-DEV/npm/%40malio%2Flayer-ui/-/1.4.8/layer-ui-1.4.8.tgz",
-            "integrity": "sha512-ABQmfMqJqKGGnx6kf5KK/XVuKAPWSpRHmLpS9XMg6pUH8kww8o3JoywlrlFkk9xA30zNFaehAtzV7S19E4JTlg==",
+            "version": "1.6.0",
+            "resolved": "https://gitea.malio.fr/api/packages/MALIO-DEV/npm/%40malio%2Flayer-ui/-/1.6.0/layer-ui-1.6.0.tgz",
+            "integrity": "sha512-2sN4mL1Jf984oeE4N4yEv6XFgSz0Gc+uSG+HLGfRrdzjAsMcU9hbb7HSAo3Q6MBvQHZn3ZBr1cK+VUM0kXY4NA==",
             "dependencies": {
                 "@nuxt/icon": "^2.2.1",
                 "@nuxtjs/tailwindcss": "^6.14.0",