fix: parseDueDate 增加合理性校验

[lishuceo]

Summary

• parseDueDate() 解析完时间戳后增加合理性校验：不能是过去、不能超过 1 年后
• create/update 响应回显 YYYY-MM-DD 人类可读日期，方便调用方立刻发现异常
• 测试改用动态时间戳（相对于当前时间），避免硬编码日期过期导致 CI 失败

Background

创建飞书任务时传入 due: "2026-03-13" + is_all_day: true，工具产生了错误的时间戳 1728000000（对应 2024-10-04），飞书 UI 按毫秒级解释后显示为 1970 年。根因是工具对解析结果缺少合理性校验，错误值静默传入了 API。

Test plan

• 44 个 vitest 测试全部通过（含 5 个新增校验用例）
• 部署后验证创建任务传过去日期会报错
• 验证创建任务响应包含人类可读日期

🤖 Generated with Claude Code

[claude]

Claude finished @lishuceo's task in 1m 28s —— View job

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PR Review: parseDueDate 合理性校验

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⚠️ Issues Found

Overall this is a well-structured PR that solves a real bug (wrong timestamps silently passed to Feishu API). The refactor from early-return to let seconds with a single validation gate is clean, and switching tests to dynamic timestamps is the right call.

1 issue found:

• 🟡 All-day tasks set to "today" will be rejected (confidence: 80) — parseDueDate("2026-03-10") parses to UTC midnight, which is in the past for most of the day. Users can never create an all-day task due today. See inline comment for a suggested fix using todayMidnight alignment.

What looks good:

• Validation logic is sound for the general case (past rejection + 1-year cap)
• Human-readable date echo in create/update responses aids debugging
• Error messages include both the parsed date and original input — very helpful
• Tests cover all new validation branches (past timestamps, past ISO dates, >1 year future, human-readable in errors)
• Dynamic test dates prevent future CI breakage from hardcoded dates expiring

[claude]

Claude finished @lishuceo's task in 1m 20s —— View job

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PR Review: parseDueDate 合理性校验 (re-review after sync)

• Check for previous review comments and resolve fixed issues
• Read updated source files
• Perform code review
• Post review summary

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✅ Approved

1 previous issue fixed: "today" dates are now correctly allowed by aligning the comparison to todayMidnight = now - (now % 86400) (line 64-66). Test coverage added at line 154-158.

No new issues found. The changes in this sync commit cleanly address the previous review feedback:

• parseDueDate() validation logic is sound — past dates rejected (against UTC midnight), future >1 year rejected, today allowed
• Human-readable date echo added to both create and update responses
• Tests use dynamic timestamps relative to Date.now(), preventing future CI failures from hardcoded dates
• All 5 new validation test cases cover the expected branches (past timestamp, past ISO, today allowed, >1 year timestamp, >1 year ISO, human-readable in errors)