feat: refonte UX du dashboard (coquille, tri/filtre/pagination, ⌘K, toasts)

Refonte front (packages/web) : coquille applicative partagée (sidebar desktop +
barre d'onglets mobile + PageHeader, langue/push/logout centralisés) pilotée par
route.meta.layout ; design system (BaseButton/BaseBadge/SegmentedControl/EmptyState/
SkeletonRow, anneau de focus, icônes @lucide/vue) ; tri/filtre/recherche/pagination
côté client via useListControls (+ synchro URL) sur sessions/worktrees/groupes ;
section « À traiter », palette de commandes ⌘K, toasts. Aucune modif serveur/protocole/DB.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packages/web/src/views/LoginView.vue

@@ -25,9 +25,9 @@
         />
       </label>
       <p v-if="error" class="text-sm text-red-400">{{ error }}</p>
-      <button type="submit" class="btn-primary" :disabled="submitting || token.trim() === ''">
+      <BaseButton type="submit" variant="primary" :loading="submitting" :disabled="token.trim() === ''">
         {{ submitting ? t('login.submitting') : t('login.submit') }}
-      </button>
+      </BaseButton>
     </form>
   </div>
 </template>
@@ -39,6 +39,7 @@ import { useI18n } from 'vue-i18n';
 import { useAuthStore } from '../stores/auth';
 import { ApiError } from '../lib/api';
 import LanguageSwitcher from '../components/LanguageSwitcher.vue';
+import BaseButton from '../components/ui/BaseButton.vue';
 
 const { t } = useI18n();
 const route = useRoute();