Allow non-modifier keyboard keys to be used as conditions for trigger activation

### Discussed in https://github.com/taj-ny/InputActions/discussions/448

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<sup>Originally posted by **RevHarryPowell** May  2, 2026</sup>
Currently the only accepted keyboard modifiers are alt, ctrl, meta, & shift, according to the wiki. Would it be possible to allow for any key to be used as a modifier?</div>