New features and improvements

[chaqchase]

This pull request introduces several new features and improvements to the cronbake package, focusing on enhanced scheduling controls, robust overrun protection, and a pluggable persistence system. It also updates documentation, fixes cron parsing and type issues, and improves packaging and public API surface.

Major features and improvements:

Scheduling Controls & Overrun Protection

• Added immediate and delay options to allow the first cron callback to run immediately or after a configurable delay. Introduced overrunProtection (default: true) to prevent overlapping executions if a previous run is still in progress. These features are now documented and available in both the API and README usage examples. [1] [2] [3] F1ca759aL4R4, [4] [5]

Persistence System

• Refactored persistence to use pluggable providers. Added FilePersistenceProvider (JSON on disk) and RedisPersistenceProvider (single-key JSON via injected client). The persistence system now uses a provider interface, and the public API exports these providers for external use. Documentation and usage examples in the README have been updated accordingly. [1] [2] [3] [4] [5] [6]

Cron Expression & Type Fixes

• Improved cron expression parsing, including correct mapping for @on_<day>, fixes for @every_<n>_months and @every_<n>_dayOfWeek, and replaced the custom Timer type with ReturnType<typeof setTimeout|setInterval> for better portability. [1] [2] [3] [4] [5]

Documentation & Examples

• Updated the README and CHANGELOG with new features, usage examples for immediate/delayed runs, overrun protection, and persistence providers. Added notes about new metrics (skippedExecutions) and clarified persistence options. [1] F1ca759aL4R4, [2] [3] [4]

Packaging & Public API

• Changed package access from restricted to public and fixed build issues by replacing path aliases (@/lib) with relative imports. Ensured new persistence providers and types are exported from the main API. [1] [2] [3] [4]

These changes collectively make cronbake more flexible, robust, and easier to integrate with various persistence backends, while improving reliability and developer experience.