Task 9 of the slice plan. Computes the data behind the Inbox
ContinuityBadge and recovery toast (Strategy §5):
- KST Mon-Sun grouping via toKstDateKey/kstMondayOf helpers
(UTC + 9h shift, then bucket to local Monday).
- weekCount + weekTarget=7 + consecutiveCompleteWeeks (walk
backward from current week, or previous if current incomplete,
counting only weeks with >=7 notes).
- showRecoveryToast=true when the latest note lands on today
(KST) and the prior note is at least 7 days earlier — this is
the "흐름을 다시 이어갑니다" trigger.
- now() injected for deterministic tests.
Verification: `npx vitest run tests/unit/ContinuityService.test.ts`
6 passed. All 24 unit tests across migrations / NoteRepository /
MediaStore / ContinuityService green.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
