[vycdev2]

Summary

• Reject impossible slash-formatted calendar dates in time estimates rather than silently rolling to another month.
• Keep valid slash-formatted dates and existing ISO parsing intact; add regression coverage and changelog entry.

Verification

• npm run typecheck — passed.
• npm test — passed (427 tests); regression failed on the unchanged implementation before the fix.
• npm run compile — passed.
• npm run format:check — passed.
• git diff --check — passed.

Risk

• Low: applies strict validation to fully specified slash-formatted calendar dates in the time parser.

This was generated by an AI agent (vycdev2). Please verify any changes before merging or applying.

[vycdev]

Reviewed and fixed a validation gap: inputs such as 2020/2/30 and 2020/02/30 9:00 bypassed the new guard and still silently became March 1. Validation now checks the calendar components for supported one- or two-digit month/day/hour forms, while preserving valid padded and unpadded leap dates. The same check handles the existing dash form consistently.

Added a regression covering padded/unpadded slash and dash inputs, invalid leap dates, and valid date/time counterparts. The regression reproduced the rollover before the fix. Updated this branch with the merged Markdown fix from develop; validation passed on the combined head: typecheck, 429 tests, webpack development build, format check, and git diff whitespace check.