LabChronyx: Cron, in plain English

Chronyx translates cron expressions into plain English and shows the next run times. A from-scratch parser turns each field into a value set, and the matching logic correctly honours cron's surprising day-of-month/day-of-week OR rule that catches most implementations out. It is a from-scratch, dependency-free build covered by 20 unit tests that you can download and run locally.