[Feature]: Alt Modifier + Vertical Scrolling when Scrolling With Thumbwheel on MX Mice

### Pre-flight checklist

- [x] I searched existing issues and the [Roadmap](https://github.com/AprilNEA/OpenLogi#roadmap), and this isn't already tracked.

### Problem / motivation

I'm wanting to be able to substitute scrolling using the thumb scroll wheel with vertical scrolling while the ALT modifier is pressed for a nicer workflow (First use case being FL Studio note pitching, which would exceptionally smooth and a good use of the MX mouse layout). This is specifically what I was hoping OpenLogi could do that Logi Options couldn't when I first installed.

### Proposed solution

Granular, input options for vertical scrolling with a certain input modifier (also requested in [Feature]: Map thumbwheel rotation to Ctrl + vertical mouse wheel for native zoom #377) would allow for more opaque options than the likes of horizontal scroll and or the fixed options provided; a vertical scroll with input modifier under thumbwheel scroll options (or just scroll up and down with CTRL and ALT) could quite simply cover these use cases.

### Alternatives considered

_No response_

### Related area(s)

- [ ] GUI
- [ ] CLI
- [x] Button actions / remapping
- [ ] DPI
- [ ] SmartShift
- [ ] Per-application profiles
- [ ] Configuration (TOML)
- [ ] Auto-update
- [ ] Other

### Additional context

_No response_

Start by tracing the button actions/remapping implementation and how thumbwheel input is handled, then compare the related request in issue #377. The work is done when ALT plus thumbwheel rotation produces vertical scrolling while normal thumbwheel behavior remains unchanged.

Written by the indexing model from the issue text.