Initialize weight table when signing up (Backend)

[yjeong-k]

PR Title: Initialize weight table when signing up (Backend)

Related Issue(s):

PR Description:

회원가입 시 웨이트 테이블 초기값 저장해두도록 변경하였습니다

Changes Included:

• Added new feature(s)
• Fixed identified bug(s)
• Updated relevant documentation

Notes for Reviewer:

Any specific instructions or points to be considered by the
reviewer.

Reviewer Checklist:

• Code is written in clean, maintainable, and idiomatic form.
• Automated test coverage is adequate.
• All existing tests pass.
• Manual testing has been performed to ensure the PR works as expected.
• Code review comments have been addressed or clarified.

Additional Comments:

Add any other comments or information that might be useful for the
review process.

[JH747]

코드와 영상 확인하였습니다.
고생하셨습니다.