bug(windows): mnemonic layout doesn't support Ctrl and Alt keys

### Describe the bug

From the community site: https://community.software.sil.org/t/ctrl-key-mnemonic-sil-ipa-not-working/10301

> Hello everyone. I am currently using the SIL IPA keyboard. My standard layout is Dvorak. Shifting works, caps lock works, but CTRL + any key uses the qwerty layout.
>
> Any help would be great, thank you!

### Reproduce the bug

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### Expected behavior

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### Related issues

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### Keyman apps

- [ ] Keyman for Android
- [ ] Keyman for iPhone and iPad
- [ ] Keyman for Linux
- [ ] Keyman for macOS
- [x] Keyman for Windows
- [ ] Keyman Developer
- [ ] KeymanWeb
- [ ] Other - give details at bottom of form

### Keyman version

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### Operating system

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### Device

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### Target application

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### Browser

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### Keyboard name

_No response_

### Keyboard version

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### Language name

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### Additional context

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