can 'Remap a shortcut' add a feature：caplos

### Description of the new feature / enhancement

windows 11
i want use capslock + 'ijkl' to move the cursor when typing.
but when i try to use the remap a shortcut in powertoys and add the capslock, it refused and prompted that: Shortcut keys must start with a modifier key.
so i wish this feature can be added cause i dont want to download and use a new software in my computer.
Thank you.

### Scenario when this would be used?

when i push down capslock, it is used like a fn key.
in this time, i push 'i', the cursor goes up, 'k' down, 'j' legt, 'l' right and other function.
so when typing we dont need to move out hand to Arrow keys.

### Supporting information

i learned this point in this video https://www.douyin.com/jingxuan?modal_id=7662776322191576335
I would be extremely grateful if this feature could be added in remap a shortcut or some other place.

Start by reviewing PowerToys Keyboard Manager's “Remap a shortcut” flow and the validation that requires a modifier key. Determine how Caps Lock plus I/J/K/L should be represented and whether the behavior belongs in shortcut remapping or another keyboard feature. Done means the requested cursor movements work reliably on Windows 11 without breaking normal key behavior.

Written by the indexing model from the issue text.