Add marathon finish button and system

frontend/src/pages/MarathonPage.tsx

@@ -9,7 +9,7 @@ import { useConfirm } from '@/store/confirm'
 import { EventBanner } from '@/components/EventBanner'
 import { EventControl } from '@/components/EventControl'
 import { ActivityFeed, type ActivityFeedRef } from '@/components/ActivityFeed'
-import { Users, Calendar, Trophy, Play, Settings, Copy, Check, Loader2, Trash2, Globe, Lock, CalendarCheck, UserPlus, Gamepad2, ArrowLeft, Zap } from 'lucide-react'
+import { Users, Calendar, Trophy, Play, Settings, Copy, Check, Loader2, Trash2, Globe, Lock, CalendarCheck, UserPlus, Gamepad2, ArrowLeft, Zap, Flag } from 'lucide-react'
 import { format } from 'date-fns'
 
 export function MarathonPage() {
@@ -25,6 +25,7 @@ export function MarathonPage() {
   const [copied, setCopied] = useState(false)
   const [isDeleting, setIsDeleting] = useState(false)
   const [isJoining, setIsJoining] = useState(false)
+  const [isFinishing, setIsFinishing] = useState(false)
   const [showEventControl, setShowEventControl] = useState(false)
   const activityFeedRef = useRef<ActivityFeedRef>(null)
 
@@ -125,6 +126,31 @@ export function MarathonPage() {
     }
   }
 
+  const handleFinish = async () => {
+    if (!marathon) return
+
+    const confirmed = await confirm({
+      title: 'Завершить марафон?',
+      message: 'Марафон будет завершён досрочно. Участники больше не смогут выполнять задания.',
+      confirmText: 'Завершить',
+      cancelText: 'Отмена',
+      variant: 'warning',
+    })
+    if (!confirmed) return
+
+    setIsFinishing(true)
+    try {
+      const updated = await marathonsApi.finish(marathon.id)
+      setMarathon(updated)
+      toast.success('Марафон завершён')
+    } catch (err: unknown) {
+      const error = err as { response?: { data?: { detail?: string } } }
+      toast.error(error.response?.data?.detail || 'Не удалось завершить марафон')
+    } finally {
+      setIsFinishing(false)
+    }
+  }
+
   if (isLoading || !marathon) {
     return (
       <div className="flex justify-center py-12">
@@ -216,6 +242,18 @@ export function MarathonPage() {
                 </Button>
               </Link>
 
+              {marathon.status === 'active' && isOrganizer && (
+                <Button
+                  variant="secondary"
+                  onClick={handleFinish}
+                  isLoading={isFinishing}
+                  className="text-yellow-400 hover:text-yellow-300 hover:bg-yellow-900/20"
+                >
+                  <Flag className="w-4 h-4 mr-2" />
+                  Завершить
+                </Button>
+              )}
+
               {canDelete && (
                 <Button
                   variant="ghost"