Implement completion screen in MainPage component to celebrate task achievements. Introduce state management for completed chains and enhance UI with congratulatory messages and a continue button. Remove unused notification logic to streamline the component.

src/pages/main/main.tsx

@@ -1,7 +1,10 @@
 import React, { useEffect, useRef, useState } from 'react'
 import {
   Box,
+  Button,
+  Heading,
   Text,
+  VStack,
 } from '@chakra-ui/react'
 import { Alert } from '@chakra-ui/react/alert'
 
@@ -16,14 +19,13 @@ const SELECTED_CHAIN_KEY = 'challengeSelectedChainId'
 const SELECTED_TASK_KEY = 'challengeSelectedTaskId'
 
 export const MainPage = () => {
-  const { nickname, eventEmitter, chains } = useChallenge()
+  const { nickname, chains } = useChallenge()
   const [selectedChain, setSelectedChain] = useState<ChallengeChain | null>(null)
   const [selectedTask, setSelectedTask] = useState<ChallengeTask | null>(null)
+  const [completedChainName, setCompletedChainName] = useState<string | null>(null)
   const [isOffline, setIsOffline] = useState(() =>
     typeof navigator !== 'undefined' ? !navigator.onLine : false,
   )
-  const [notification, setNotification] = useState<{ status: 'success' | 'warning'; title: string; description?: string } | null>(null)
-  const notificationTimeoutRef = useRef<number | null>(null)
   const hasRestoredState = useRef(false)
 
   // Восстановление состояния при загрузке
@@ -66,7 +68,8 @@ export const MainPage = () => {
       setSelectedTask(nextTask)
       localStorage.setItem(SELECTED_TASK_KEY, nextTask.id)
     } else {
-      // Цепочка завершена, возвращаемся к выбору
+      // Цепочка завершена - показываем экран поздравления
+      setCompletedChainName(selectedChain.name)
       setSelectedChain(null)
       setSelectedTask(null)
       localStorage.removeItem(SELECTED_CHAIN_KEY)
@@ -74,33 +77,10 @@ export const MainPage = () => {
     }
   }
 
-  useEffect(() => {
-    const unsubscribe = eventEmitter.on('submission_completed', (event) => {
-      const submission = (event.data as { submission?: { status: string; attemptNumber: number } })?.submission
-      const accepted = submission?.status === 'accepted'
+  const handleContinueAfterCompletion = () => {
+    setCompletedChainName(null)
+  }
 
-      if (!accepted) {
-        return
-      }
-
-      const title = 'Задание принято'
-      const description = submission ? `Попытка №${submission.attemptNumber}` : undefined
-
-      if (notificationTimeoutRef.current) {
-        window.clearTimeout(notificationTimeoutRef.current)
-      }
-
-      // setNotification({ status: 'success', title, description })
-      notificationTimeoutRef.current = window.setTimeout(() => setNotification(null), 4000)
-    })
-
-    return () => {
-      unsubscribe()
-      if (notificationTimeoutRef.current) {
-        window.clearTimeout(notificationTimeoutRef.current)
-      }
-    }
-  }, [eventEmitter])
 
   useEffect(() => {
     const handleOnline = () => setIsOffline(false)
@@ -120,6 +100,61 @@ export const MainPage = () => {
     return <LoginForm />
   }
 
+  // Если цепочка завершена, показываем экран поздравления
+  if (completedChainName) {
+    return (
+      <>
+        <Header />
+        <Box bg="gray.50" minH="100vh" display="flex" alignItems="center" justifyContent="center" px={4}>
+          <Box
+            bg="white"
+            borderWidth="2px"
+            borderRadius="xl"
+            borderColor="green.300"
+            p={10}
+            maxW="600px"
+            w="full"
+            textAlign="center"
+            shadow="lg"
+          >
+            <VStack gap={6}>
+              <Text fontSize="6xl">🎉</Text>
+              <Heading size="xl" color="green.600">
+                Поздравляем!
+              </Heading>
+              <Text fontSize="lg" color="gray.700">
+                Вы успешно выполнили все задания
+              </Text>
+              <Box 
+                bg="green.50" 
+                borderRadius="lg" 
+                px={6} 
+                py={3}
+                borderWidth="1px"
+                borderColor="green.200"
+              >
+                <Text fontSize="xl" fontWeight="bold" color="green.700">
+                  {completedChainName}
+                </Text>
+              </Box>
+              <Text fontSize="md" color="gray.600">
+                Отличная работа! Вы можете продолжить обучение, выбрав другую цепочку заданий.
+              </Text>
+              <Button
+                colorScheme="green"
+                size="lg"
+                onClick={handleContinueAfterCompletion}
+                mt={4}
+              >
+                Продолжить
+              </Button>
+            </VStack>
+          </Box>
+        </Box>
+      </>
+    )
+  }
+
   // Если цепочка не выбрана, показываем селектор цепочек
   if (!selectedChain) {
     return (
@@ -138,16 +173,6 @@ export const MainPage = () => {
       <Header chainName={selectedChain.name} taskProgress={taskProgress} />
       <Box bg="gray.50" minH="100vh" py={4} px={{ base: 4, md: 8 }}>
         <Box maxW="1200px" mx="auto">
-          {notification && (
-            <Alert.Root status={notification.status} borderRadius="md" mb={4}>
-              <Alert.Indicator />
-              <Box ml={3}>
-                <Text fontWeight="semibold">{notification.title}</Text>
-                {notification.description && <Text fontSize="sm">{notification.description}</Text>}
-              </Box>
-            </Alert.Root>
-          )}
-
           {isOffline && (
             <Alert.Root status="warning" borderRadius="md" mb={4}>
               <Alert.Indicator />