bug(windows): RALT + Key that outputs a deadkey is interpreted as RALT menu key by Qt-based text widget

### Describe the bug

I’m using the _Greek Polytonic Plus_ keyboard on Windows 11. On that keyboard, pressing AltRight+i a should give me an "alpha with iota subscript”, i.e., ᾳ (where the iota appears below the alpha); instead, AltRight+i is intercepted by the editors I use (TeXworks and TeXstudio), where it opens the File menu instead. **Note:** I have made sure that neither editor uses AltRight+i as a default key-combination.

Since this happens
1. not only with TeXworks but also with TeXstudio; and
2. only when the Greek Polytonic Plus keyboard is enabled,

**I suspect that this might happen in any application that uses a Qt-based text widget** (TeXworks and TeXstudio), but not in applications that don’t: Notepad++, for example, which uses the Scintilla text widget (not Qt-based, on Windows), does not have this problem.

[Marc suggested](https://community.software.sil.org/t/key-combination-intercepted-by-document-editor-before-reaching-keyman/10425/7) that I file a bug to have this investigated.

### Reproduce the bug

1. Open up a Qt-based text editor, e.g., TexWorks (in my case).
2. In Keyman, switch to _Greek Polytonic Plus_ keyboard.
3. Press AltRight+i a

### Expected behavior

ᾳ (alpha with an "iota subscript" beneath it) _should_ appear.

But it doesn't: Instead, **File** (in the TexWorks menu bar) is highlighted — and pressing Enter will pull down the **File** menu.

### Related issues

_No response_

### 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

18.0.238

### Operating system

Windows 11

### Device

_No response_

### Target application

TexWorks

### Browser

_No response_

### Keyboard name

greek_polytonic-plus

### Keyboard version

2.0

### Language name

_No response_

### Additional context

_No response_