Feat: 채팅방 모달 컴포넌트 생성 (#26)

- 채팅 기능을 위한 모달 컴포넌트 구현
- 모달 열기 및 닫기 상태 관리 로직 추가
- 메시지 리스트와 입력창 UI를 구성하는 ChatRoom 컴포넌트 포함

src/components/pages/community/modal/ChatRoomModal.tsx

@@ -0,0 +1,93 @@
+import React from 'react';
+import styled from 'styled-components';
+import ChatRoom from '../../../common/ChatRoom'; // 채팅방 컴포넌트
+import { WebSocketService } from '../../../../utils/webSocket';
+
+interface ChatRoomModalProps {
+  chatRoomId: string;
+  chatRoomTitle: string;
+  isOpen: boolean;
+  onClose: () => void;
+  webSocketService: WebSocketService;
+}
+
+const ChatRoomModal: React.FC<ChatRoomModalProps> = ({
+  isOpen,
+  onClose,
+  chatRoomId,
+  chatRoomTitle,
+}) => {
+  if (!isOpen) return null;
+
+  return (
+    <ModalOverlay>
+      <ModalContainer>
+        <ModalHeader>
+          <ModalTitle>{chatRoomTitle}</ModalTitle>
+          <ModalCloseButton onClick={onClose}>&times;</ModalCloseButton>
+        </ModalHeader>
+        <ModalContent>
+          <ChatRoom chatRoomId={chatRoomId} />
+        </ModalContent>
+      </ModalContainer>
+    </ModalOverlay>
+  );
+};
+
+export default ChatRoomModal;
+
+const ModalOverlay = styled.div`
+  position: fixed;
+  top: 0;
+  left: 0;
+  width: 100%;
+  height: 100%;
+  background-color: rgba(0, 0, 0, 0.5);
+  display: flex;
+  justify-content: center;
+  align-items: center;
+  z-index: 9999;
+`;
+
+const ModalContainer = styled.div`
+  width: 90%;
+  max-width: 600px;
+  background-color: #fff;
+  border-radius: 10px;
+  overflow: hidden;
+  display: flex;
+  flex-direction: column;
+  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
+`;
+
+const ModalHeader = styled.div`
+  padding: 16px;
+  background-color: #f7f7f7;
+  border-bottom: 1px solid #ddd;
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+`;
+
+const ModalTitle = styled.h2`
+  font-size: 18px;
+  font-weight: bold;
+  color: #333;
+`;
+
+const ModalCloseButton = styled.button`
+  background: none;
+  border: none;
+  font-size: 20px;
+  cursor: pointer;
+  color: #666;
+  &:hover {
+    color: #333;
+  }
+`;
+
+const ModalContent = styled.div`
+  flex: 1;
+  padding: 16px;
+  overflow-y: auto;
+`;