feat: Dockerfile에 Grafana OTel Java agent 추가

[unam98]

작업 배경

• Render 배포로 전환하면서 원래 EC2용으로 준비했던 Grafana Cloud 모니터링(JVM/APM 지표) 설정이 누락됨

변경 사항

영역	내용
Dockerfile	빌드 시점에 grafana-opentelemetry-java.jar 다운로드 + ENTRYPOINT에 -javaagent 추가

영향 범위

• 로컬 빌드/실행 시 검증: 이미지 빌드 성공, agent jar(24MB) 이미지 내 존재 확인
• Render는 자체 Docker Command 오버라이드를 쓰므로, 이 PR 머지와 별개로 Render 대시보드에서 Docker Command + 환경변수도 함께 갱신 예정
• EC2 배포 경로(deploy.sh)는 별도 로직(agent 파일 유무 조건부 감지)이라 이 변경과 무관, 계속 정상 동작

Test Plan

• docker build 로컬 성공 확인
• 이미지 내 grafana-opentelemetry-java.jar 존재 확인
• Render 재배포 후 Grafana Cloud에 실제 메트릭 수집 확인

🤖 Generated with Claude Code

[coderabbitai]

Warning

Review limit reached

@unam98, you've reached your PR review limit, so we couldn't start this review.

Next review available in: 50 minutes

Enable usage-based reviews in Billing to review now. Otherwise, wait until the next included review is available.
You're only billed for reviews past your plan's rate limits ($0.25/file).

How can I continue?

After more reviews become available, a review can be triggered using the @coderabbitai review command as a PR comment. Alternatively, push new commits to this PR.

To avoid repeated limits, reduce automatic review volume by pausing incremental auto-reviews earlier, using label-based review opt-in, excluding WIP or generated PR titles, or requesting reviews manually when the PR is ready. If your team needs uninterrupted high-volume reviews, an organization admin can enable usage-based reviews.

How do review limits work?

CodeRabbit enforces per-developer PR review limits for each organization. Most developers receive the normal plan review availability.

For paid Pro and Pro+ PR reviews, CodeRabbit uses adaptive limits for sustained high-volume activity. When a developer's recent PR review activity reaches the 95th percentile or higher among CodeRabbit users, additional reviews become available more gradually as earlier reviews age out of the rolling window.

Please refer docs for additional details.

Review details

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: 9a95fe7e-60b0-441d-856d-024e075524cc

📥 Commits

Reviewing files that changed from the base of the PR and between 253bc7d and 5acfd0e.

📒 Files selected for processing (1)

• Dockerfile

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch feat/render-otel-agent

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}