refactor: improve docs

docs/data-sources/workspace_preset.md

@@ -80,5 +80,5 @@ See https://en.wikipedia.org/wiki/List_of_tz_database_time_zones for a complete
 
 Required:
 
-- `cron` (String) A cron expression that defines when this schedule should be active. The cron expression must be in the format "* HOUR * * DAY-OF-WEEK" where HOUR is 0-23 and DAY-OF-WEEK is 0-6 (Sunday-Saturday). The minute, day-of-month, and month fields must be "*".
+- `cron` (String) A cron expression that defines when this schedule should be active. The cron expression must be in the format "* HOUR DOM MONTH DAY-OF-WEEK" where HOUR is 0-23, DOM (day-of-month) is 1-31, MONTH is 1-12, and DAY-OF-WEEK is 0-6 (Sunday-Saturday). The minute field must be "*" to ensure the schedule covers entire hours rather than specific minute intervals.
 - `instances` (Number) The number of prebuild instances to maintain during this schedule period.