enhancement: add human-readable schedule description

[CybotTM]

Description

Users may want to display cron schedules in human-readable format for UIs or logs.

Current Limitation

entry := c.Entry(id)
fmt.Println(entry.Schedule)  // Just prints struct, not useful

Proposed Enhancement

// Method on Schedule interface
type Schedule interface {
    Next(time.Time) time.Time
    Description() string  // New method
}

// Usage
entry := c.Entry(id)
desc := entry.Schedule.Description()
// Returns: "Every 5 minutes" or "At 2:30 AM on weekdays"

// Standalone function for specs
desc := cron.DescribeSpec("0 30 2 * * MON-FRI")
// Returns: "At 2:30 AM, Monday through Friday"

Examples

Spec	Description
* * * * *	Every minute
0 * * * *	Every hour
0 0 * * *	Every day at midnight
0 0 1 * *	First day of every month at midnight
*/15 * * * *	Every 15 minutes
0 9-17 * * MON-FRI	Every hour from 9 AM to 5 PM, Monday to Friday

Severity

🟢 Low - UX improvement

Found By

Pre-1.0 release code review with Zen/Gemini