[#13] 스케쥴 서비스 코드 로직 대폭 수정 및 미팅서비스 테스트 완료

config/sequelize.js

controllers/meetingController.js

dtos/CreateMeetingRequestDTO.js

dtos/MeetingDetailResponseDTO.js

dtos/MeetingResponseDTO.js

middlewares/auth.js

models/Friend.js

models/index.js

models/meeting.js

models/meetingParticipant.js

models/schedule.js

package-lock.json

package.json

services/meetingService.js

services/meetingService.test.js

services/schedule.test.js

services/scheduleService.js