[fix] Modify unique constraints from PortRequests entity

[kwdahun]

🌱 관련 이슈

• close : [feat] Add port usage table per request (PortRequests table) #118

🌱 작업 사항

• 다른 서버 도메인이더라도 (LAB/FARM이 다르더라도) port_number의 unique constraint에 의해 같은 포트를 기록할 수 없는 데이터베이스 구조 수정
• rsgroup_id를 외래키로 가져와서 (rsgroup_id, port_number)를 composite unique constraint로 구성

[Copilot]

Pull Request Overview

This PR modifies the unique constraint on the PortRequests entity to allow the same port number to be used across different resource groups. The change addresses a database constraint issue where different server domains (LAB/FARM) couldn't use the same port numbers.

• Removes the unique constraint from the port_number column alone
• Introduces a composite unique constraint on (port_number, rsgroup_id) combination
• Adds a new ManyToOne relationship with ResourceGroup entity

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[saokiritoni]

굿 !