Hue: Added user-friendly cron scheduling explanations to the Oozie Coordinator Editor

[NadafMM]

What changes were proposed in this pull request?

Issue: #4346
This PR improves the Oozie Coordinator scheduling UI by providing real-time, human-readable explanations of cron expressions and displaying the next scheduled run time. This helps users verify their schedules without relying on external tools.

Additionally, this PR fixes a misleading documentation link in the UI. The existing "Check syntax ?" link pointed to Quartz (6-field) documentation, but Oozie uses standard 5-field cron. The link has been updated to point to the standard Wikipedia cron documentation.

Example Behavior:
When a user enters a cron expression like 0 12 * * 1-5, the UI will dynamically render underneath it:

At 12:00 PM, Monday through Friday
Next run: Jul 13, 2026, 12:00 PM

Key changes:

• Added cronExpressionUtils.ts utilizing cronstrue and cron-parser to generate human-readable descriptions and calculate next run times.
• Updated coordinator-editor.ko.js and common_scheduler.inc.mako to bind and display the cron explanation dynamically in the UI.
• Updated help links in coordinator_utils.mako and common_scheduler.inc.mako.
• Added Jest unit tests for the new utility functions.

How was this patch tested?

• Unit Tests: Added and ran Jest tests for cronExpressionUtils.test.ts. All 5 tests pass successfully, covering valid expressions, invalid expressions, and edge cases.
• Manual UI Testing: Ran the Hue application locally. Verified that when creating/editing an Oozie Coordinator, typing a valid cron expression dynamically updates the UI with the correct English description and the next run time. Invalid expressions are handled gracefully. Verified the updated documentation links open the correct standard cron documentation.

(InProgress)
Screenshots: to be attached