Feature: add jenkins-style H token support

[Zer0AlmostNull]

This PR adds support for the H (hash) symbol in the minute and hour fields of cron schedules, following the same approach used by Jenkins.

Motivation
When multiple jobs share the same schedule (for example, "0 * * * *"), they all run at the same time. If those jobs are computationally heavy, this can cause noticeable CPU usage spikes.

The H symbol addresses this by allowing the scheduler to choose a stable, deterministic "random" time for each job, spreading execution more evenly over time without requiring manual offsets.

How it works

• A hash is calculated based on the function name and the corresponding cron field.
• Each H token in the schedule is replaced with a deterministic pseudo-random value derived from that hash.

Additional notes

• Unit tests were generated with the help of Microsoft Copilot

I'm open to feedback and suggestions on the implementation details.