Comment Navigation with Volume Buttons

Other clients like Eternity and Summit allow you to navigate comments with the physical volume buttons on the phone and I would like to see this feature in Voyager.

Start by locating the existing comment-navigation entry point and the app's native input integration. Check how physical volume-button events can be observed on the supported phone platforms, then connect them to next and previous comment navigation. Done means volume buttons navigate comments reliably without breaking their normal behavior elsewhere.

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