feat(projects) : add per-project task statuses and split project detail into sub-pages

Move project detail from [id].vue to [id]/ directory with Kanban, Groups
and Statuses sub-pages. Add project filter on task statuses service and
drawer. Remove global statuses tab from admin.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/pages/admin.vue

@@ -19,7 +19,6 @@
         </div>
 
         <div class="mt-6">
-            <AdminStatusTab v-if="activeTab === 'statuses'" />
             <AdminEffortTab v-if="activeTab === 'efforts'" />
             <AdminPriorityTab v-if="activeTab === 'priorities'" />
             <AdminTypeTab v-if="activeTab === 'types'" />
@@ -32,7 +31,6 @@
 useHead({ title: 'Administration' })
 
 const tabs = [
-    { key: 'statuses', label: 'Statuts' },
     { key: 'efforts', label: 'Efforts' },
     { key: 'priorities', label: 'Priorités' },
     { key: 'types', label: 'Types' },
@@ -41,5 +39,5 @@ const tabs = [
 
 type TabKey = typeof tabs[number]['key']
 
-const activeTab = ref<TabKey>('statuses')
+const activeTab = ref<TabKey>('efforts')
 </script>