Can't use a string literal to define the `storage` option when used with `TypeScript`

[brionmario]

Is your suggestion related to an experience ? Please describe.

An enum is used in the MainThreadClientConfig & WebWorkerClientConfig. This makes the DevEx a bit hard since we can't simply use webWorker or sessionStorage when passing the configuration.

Describe the improvement

Give the ability to pass the storage as a string from MainThreadClientConfig & WebWorkerClientConfig interfaces.

Additional context

N/A