Convert constructors into primary constructors
Simplified logic with use of ??, ??= and method groups
Cleaned up redundant conditional access qualifiers
* Added an option for modders to add their own Data handlers for ItemEventRouter handling serialization
* Made return type for func nullable
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Co-authored-by: Alex <clodanSPT@hotmail.com>
Co-authored-by: Alex <alex@dm-me-for-questions.com>