Portal redesign from template, real-data pages, test suite, Celery config

- templates: new shell from ACORE-template (mobile sidebar + bottom nav,
  themes, wallpaper, user dropdown), Django-ized nav with push-url;
  login rebranding; ACORE-template/ gitignored
- new pages wired to real data: databases (Directory types/counts),
  it-support (Ticket create form + my tickets), dashboard (live counters),
  structure (departments with head heuristic + pharmacy staffing status);
  static mockups for news/tasks/email/chat/purchases/hr-portal/help
- tests: 57 tests — ad_connector (ldap3 MOCK_SYNC client, sync scenarios,
  signals, mapping page), mattermost_connector (sync on mocks, bare-except
  regression), core (pages smoke, tickets, directories, tree rebuild)
- celery: add missing acore/celery.py app + CELERY_* settings (broker from
  env, eager mode without broker locally); wrap signal .delay calls so an
  unreachable broker no longer breaks employee saves

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

acore/settings/base.py

@@ -415,4 +415,10 @@ LOGGING = {
             'propagate': False,
         },
     },
-}
+}
+# --- Celery ---
+CELERY_BROKER_URL = env('CELERY_BROKER_URL', default='redis://localhost:6379/0')
+CELERY_RESULT_BACKEND = env('CELERY_RESULT_BACKEND', default=CELERY_BROKER_URL)
+CELERY_TIMEZONE = TIME_ZONE
+# Без брокера (локальная разработка) задачи выполняются синхронно
+CELERY_TASK_ALWAYS_EAGER = env.bool('CELERY_TASK_ALWAYS_EAGER', default=False)