Add unit tests for module targeting Windows

[vmoroz]

Proposal

Currently the Windows version of the module is not being tested. We must add the unit tests to keep this code healthy.

Alternatives

No response

Implementation Details

No response

Additional Context

No response

[hiSandog]

It would help to split the desired coverage into the shared JS contract and the Windows native implementation, then reuse the existing platform-agnostic test cases wherever possible. The Windows CI matrix should state architecture and packaging mode, since path and app-container behavior can differ. A first milestone covering set/get/remove/multi operations plus error propagation would give this issue a concrete scope.