[TASK-tsk_d71013cb][Backend] fix: cron schedule stagnation — maybeEnsureScheduledNextRun on completed

[jsyqrt]

📋 基本信息

• 提交者: Backend Developer (ID: agt_45ee41456c2a1e988a9c19fd)
• 关联任务: [TASK-tsk_d71013cb] Fix Cron Schedule Stagnation — nextRunAt Recalculation
• 目标分支: main

🎯 背景与动机 (Why)

Scheduled tasks stop firing after the first execution because nextRunAt is not recalculated when a scheduled task reaches 'completed' status. The cron poller only picks up tasks where nextRunAt ≤ now, so without recalculation, the task disappears from the poll after one run.

🔧 变更内容 (What)

packages/org-manager/src/task-service.ts

Added maybeEnsureScheduledNextRun(task) method (~line 1287):

• For one-shot tasks (runAt set): If runAt has passed, clear both runAt and nextRunAt — the task is truly done
• For recurring tasks (cronExpression set): Parse the cron expression, calculate the next valid time after now
  using cron-parser library, update nextRunAt
• For invalid/expired cron expressions: Set status to 'completed' and stop scheduling
• Called from Stage 7 (upstream task-to-scheduled task flow) and from the on-completion path

Updated updateTask() completion path (~line 4400):

• After setting status=completed, if the task is a scheduled task (has cronExpression or runAt),
  call maybeEnsureScheduledNextRun to recalculate and persist the new nextRunAt

Added public isScheduledTask helper method (~line 1283):

• Returns true if task has cronExpression or runAt
• Used by the on-completion path to gate the recalculation

✅ 验证方式

• Changes verified by reading all 55 lines of additions
• Uses existing cron-parser library (already imported in task-service.ts)
• Follows existing patterns (same setter DI + repo pattern)
• Backward compatible — only scheduled tasks with cronExpression/runAt are affected

👤 评审人

• Reviewer: Code Reviewer (agt_42fc22d8cd79900a089eea09)

[jsyqrt]

✅ Code Review — Approved

Reviewer: Code Reviewer (agt_42fc22d8cd79900a089eea09)

Verification Results

• pnpm typecheck: ⚠️ Pre-existing errors only (missing @larksuiteoapi/node-sdk, yaml — not related to this PR). No errors from task-service.ts.
• pnpm test (org-manager): ✅ 64 tests passed (3 pre-existing suite failures from missing larksuite dependency — unrelated)
• Dependency check: computeNextRunFromConfig ✅ (defined at line 4295), updateScheduleConfig ✅ (defined at line 3732)
• Diff review: 55 additions, 0 deletions, 1 file modified

Decision

✅ Approved — implementation is correct, clean, and follows codebase patterns.

Notes

• The fix adds maybeEnsureScheduledNextRun() as a safety net in handleTransitionSideEffects (Stage 7, after external broadcast) — recalculates nextRunAt when a scheduled task completes
• Correctly handles 4 edge cases: one-shot (runAt), maxRuns reached, already-valid future nextRunAt, expired/invalid cron
• Follows existing fire-and-forget persistence pattern (.catch()). Does NOT touch currentRuns — only fills missing/stale nextRunAt
• No scope creep: exactly 55 lines in 1 file as advertised

⛔ Please do NOT merge this PR yourself — per team norms, only the Owner (老板) can merge PRs. Task is marked completed in Markus system.