New delay RuleOption

What's Changed

• Add DelayOption by @divadretlaw in #1
  Thanks you so much for bringing this!

Breaking changes

• Raised Swift 5.9 as minimum requirement
• Rule, RuleKitOption, TriggerFrequencyOption.Frequency are now Sendable
• condition closure for EventRule and ConditionRule are now marked with Sendable

New Contributors

• @divadretlaw made their first contribution in #1

Full Changelog: 0.4.1...0.5.0