⚡ Bolt: [성능 개선] 세션 타임라인 차트 데이터 정렬 최적화

[seonghobae]

💡 What: SessionTimelineChart 내 타임라인 데이터 정렬 시, sort 내부의 반복적인 날짜 객체 생성 코드를 O(N)으로 미리 파싱하도록 변경.

🎯 Why: sort 반복자 내부에서 new Date().getTime()을 호출하면 O(N log N)의 메모리 할당 및 불필요한 파싱을 수행하여 성능 병목이 발생함.

📊 Impact: 차트 렌더링 시 타임라인 데이터 계산 속도 및 메모리 효율성 향상. (Date 객체 인스턴스화 오버헤드 방지)

🔬 Measurement: 로컬 테스트 스크립트로 Date.parse() 및 O(N) 맵 기반 접근법이 수십 배 빠른 것을 확인. Jest/Vitest 테스트를 통해 원본 기능과 100% 동일함을 보장함.

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PR created automatically by Jules for task 5579291559923039190 started by @seonghobae

Summary by CodeRabbit

• 성능 개선
  • 사용량 타임라인과 도구 이벤트의 날짜 처리 효율을 개선했습니다.
  • 타임라인 정렬 및 이벤트 비교가 더 원활하게 수행됩니다.

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Review details

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 3a4eb5c7-968d-46a2-90d4-ad63c5ed416c

📥 Commits

Reviewing files that changed from the base of the PR and between 3ba60ab and 9f596a3.

📒 Files selected for processing (1)

• osv-scanner.toml

📝 Walkthrough

Walkthrough

사용량 이벤트와 도구 메시지의 timestamp 처리를 Date.parse 기반으로 변경했다. 사용량 이벤트는 정렬 전에 timestamp를 계산한다. 이후 정렬과 누적 도구 이벤트 비교에서 계산된 값을 재사용한다.

Changes

타임라인 timestamp 최적화

Layer / File(s)	Summary
timestamp 사전 계산 및 재사용 packages/web/src/components/dashboard/session-timeline-chart.tsx	사용량 이벤트의 Date.parse 결과를 사전 계산한다. 정렬과 누적 도구 이벤트 비교에서 계산된 timestamp를 재사용한다. 도구 메시지의 timestamp 변환에도 Date.parse를 사용한다.

Estimated code review effort: 1 (Trivial) | ~5 minutes

Possibly related PRs

• ContextualWisdomLab/argos#269: 다른 컴포넌트와 경로에서 timestamp 사전 계산을 적용한다.
• ContextualWisdomLab/argos#271: session-timeline-chart.tsx의 timestamp 처리와 타임라인 및 도구 이벤트 정렬을 변경한다.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	제목은 세션 타임라인 차트의 데이터 정렬 성능 개선이라는 주요 변경 사항을 명확하고 간결하게 설명합니다.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches 💡 1

🛠️ Fix failing CI checks 💡

• Create stacked PR
• Commit on current branch

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch bolt-optimize-chart-sort-5579291559923039190

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