Implemented synchronous methods for serialization and deserialization while marking the asynchronous methods as obsolete across various storage and serialization services. This includes updates to handle serialization within the Save and Load methods, enhancing performance by avoiding unnecessary Task usage.
Added tests in `Elsa.Workflows.Core.UnitTests` and `Elsa.JavaScript.UnitTests` to ensure unicode string serialization works correctly. Added a shared `UnicodeRangeGenerator` for test data generation and updated project references accordingly. Renamed `WorkflowDefinitionActivityJavaScriptHandlerTests.cs` to `ToJsonTests.cs` to reflect the focused test purpose.