[Feature Request] Separate keyboard shortcut to toggle font replacement

### Prerequisites

- [X] I [searched for any existing report](https://github.com/darkreader/darkreader/issues?q=is%3Aissue) about this feature request to avoid opening a duplicate.

### Is this feature request related to a problem?

No

### Feature Request Description

Currently, the font replacement option is in the "More" tab of the options.

It would be helpful if there was a keyboard shortcut that toggles this option alone, as there are multiple clicks required to toggle it.

### Screenshots

_No response_

### Additional Context

_No response_