What is confirmed
The demo and full 1.0 release are both officially documented, but the developer FAQ does not describe a demo-save migration workflow. That means a transfer should not be presented as supported without a primary-source instruction.
Safest next step
Keep the demo installed or preserve its save data if progress matters to you. If the developers add an import option, follow the in-game prompt or an official Steam/Discord announcement rather than moving files based on an unverified path.