[Task] 기능 / 로그아웃 시 페이지 리디렉션 / <redirection>

### ISSUE
- Group : `client`
- Type : `feature`
- Detail : 로그아웃시 페이지 리디렉션

### TODO
1. [ ] 로그아웃 성공시 렌더링 페이지로 리디렉션
2. [ ] 로그아웃 실패시 에러페이지 출력후 'myPage' 리디렉션

### Estimated time

### `1h`

### Labels
- Estimated time : `E:1h`
- Group : `client`
- Spirnt : `bare#4`
- Urgencty : `High`

Start by locating the client-side logout flow and its route definitions. Confirm which page should render after a successful logout, and ensure a failed logout shows the error page before redirecting to `myPage`; verify both outcomes through the existing client checks or manual flow.

Written by the indexing model from the issue text.