feat(web): add support for the English (India) keyboard for Windows to switch to Alt Gr layer on Keymanweb

### Is your feature request related to a problem? Please describe.

When trying to switch to the Right Alt or Alt Gr layer with the Malayalam basic keyboard on [Keymanweb](https://keymanweb.com/#ml,Keyboard_basic_kbdinmal) using the English (India) keyboard for Windows, the Alt Gr layer does not show up. Only when clicking on the OSK, does it work.

The original post - https://community.software.sil.org/t/input-handling-in-keyman-web-with-the-windows-english-india-keyboard/8466/3

### Describe the solution you'd like

_No response_

### Describe alternatives you've considered

_No response_

### Related issues

_No response_

### Keyman apps

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

### Keyman version

16.0.145 stable & 17.0.278 beta

### Operating system

Windows 10 Home version 2004 & Windows 11 Home Single Language version-23H2

### Device

Windows laptop

### Target application

_No response_

### Browser

Chrome v 122.0.6261.70, Firefox v 123.0 (64-bit), and Microsoft Edge v 122.0.2365.52

### Keyboard name

basic_kbdinmal

### Keyboard version

1.1

### Language name

Malayalam

### Additional context

_No response_