[Bug]: K400+ only has F1-F12, insert key has special function

### Pre-flight checklist

- [x] I searched [existing issues](https://github.com/AprilNEA/OpenLogi/issues?q=is%3Aissue) and this is not a duplicate.
- [x] I am on the [latest release](https://github.com/AprilNEA/OpenLogi/releases/latest) or a recent `master` build.
- [x] I quit **Logi Options+** before running OpenLogi (the two apps fight over HID++ access and only one can own a receiver at a time).

### Which part of OpenLogi?

GUI (desktop app)

### OpenLogi version

0.8.3

### Operating system

Windows

### OS version & architecture

11 x64

### Device model

K400+

### How is the device connected?

Other / not sure

### Affected area(s)

- [ ] Device discovery / detection
- [x] Button remapping
- [ ] DPI control
- [ ] SmartShift
- [ ] Per-application profiles
- [ ] Battery status
- [ ] Settings / configuration (TOML)
- [ ] Auto-update
- [ ] Menu bar / tray
- [ ] Other

### What happened?

The GUI shows clickable buttons for F1-F18, but the keyboard only has F1-F12. The insert key of the keyboard has the special function to shutdown the computer, but is not configurable in OpenLogi.

The picture of K400+ itself is correct!

### Steps to reproduce

1. Open key settings of K400+

### Diagnostics report

```markdown

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### `openlogi list` output

```text

```

### Logs

```shell

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### macOS permissions (if applicable)

- [ ] OpenLogi has **Accessibility** permission (needed to remap buttons via the event tap).
- [ ] OpenLogi has **Input Monitoring** permission (needed for Bluetooth-direct devices and capture).

Start at the GUI key-settings entry point for the K400+ and compare the displayed F1-F18 options with the keyboard's physical keys. Trace the device's button-remapping definition to determine how the Insert key's shutdown function is represented. Done means the UI shows only the available F1-F12 keys and allows the Insert function to be configured.

Written by the indexing model from the issue text.