fix(windows): use osc_to_u16 even without read scancode

[jtroo]

Describe your changes. Use imperative present tense.

This fixes an issue where keypad enter was not working correctly. I'm not entirely sure why the conditional compile branch was written in the first place; maybe I defaulted to it without thinking much about it. But it seems correct to use osc_to_u16 regardless of llhook reading mechanism given that output VK doesn't care about input reading mode.

Checklist

• Add documentation to docs/config.adoc
  • N/A
• Add example and basic docs to cfg_samples/kanata.kbd
  • N/A
• Update error messages
  • N/A
• Added tests, or did manual testing
  • Yes