v1.2.6

Patch Notes:

• Replaced JSON-based data serialization with sys.serialize and sys.deserialize functions for improved reliability and performance.
• Added defsave_ext module with encode_base64 and decode_base64 functions to convert between byte buffers and base64 strings.
• Introduced defsave.use_serialize variable to enable the new serialization method.

Benefits:

• Avoids issues with JSON encoding creating null userdata for sparse array elements.
• Eliminates the "Cannot serialise table: excessively sparse array" error when using highly sparse arrays.
• Provides a more efficient and robust approach to data serialization and deserialization.

To use the new serialization method, set defsave.use_serialize to true.

Thanks @KorolevSoftware !