pc keyboard `insert`, `ctrl`-`arrow` not passed to guest

**Describe the issue**
Events for the `insert` key on a standard pc keyboard are not seen by the vm, unless I enable usb passthrough for the keyboard - but if I do that, of course the keyboard can't work in osx apps. `ctrl`-`arrow` (either ctrl, any arrow) also don't work, with only the control event being passed through and the arrow being dropped. However, `ctrl`-`shift`-`arrow` _does_ work.

To verify whether the events are seen in the guest or not, I am using `xev -event keyboard`. Other keys cause press and release events, but the aforementioned fail.

On the host, if I open karabiner events viewer, it does show events - so it's not a case of a broken keyboard or a lack of support in osx.

I could translate `ctrl-insert` / `shift-insert` to `ctrl-x` / `ctrl-c` using karabiner but it seems like utm ought to be able to see these events. Even if I do, that doesn't solve the problem of plain `insert` not being sent - or the problem of some apps handling the insert combinations differently than they do ctrl-x/ctrl-c.

I have tried with karabiner disabled just in case it was the problem, but there was no change.

screenshot showing insert and ctrl-arrow:

While I originally saw this in a NixOS VM, I also had a Debian 12 VM from the UTM Debian 12 image. When I tried there, I was able to reproduce the issue. Both are using KDE as the UI, though I doubt that would impact keyboard events.

**Configuration**
* UTM Version: `4.6.4`
* macOS Version: `Sequoia 15.3.2`
* Mac Chip (Intel, M1, ...): `M4 Max`

**Crash log**
N/A

**Debug log**
[debug-debian12-keys.log.zip](https://github.com/user-attachments/files/20068761/debug-debian12-keys.log.zip)

**Upload VM**
N/A