v2.2.2 — Calendar event ordering fix

Calendar event ordering fix and asset refresh.

Fixes

• Calendar — same-instant events now read close-then-open. On an autoclose→next-start handoff two events share a timestamp (e.g. one food's 안전 확인 and the next food's 테스트 시작 both at 09:00). The day-detail list used to interleave the two foods awkwardly (달걀 → 소고기 → 달걀); it now lists a trial's close before the next trial's start, so events stay grouped per food (소고기 안전 확인 → 달걀 테스트 시작 → 달걀 이상 없음). Extracted as a pure sortDayEvents helper with a regression test proven to fail on the old time-only sort.

Docs & assets

• Regenerated the social-preview banner and the home/calendar screenshots so the mockups reflect the current 55-food catalog (untried count 41) and the corrected calendar ordering.
• README test count updated to 45.

npx tsc --noEmit and 45 Jest tests pass in CI.

Full changelog: v2.2.1...v2.2.2