[Feature request] Add a keybinding for "Next Sub-terminal" instead of only directional navigation

[haesbaert]

Is your feature request related to a problem? Please describe.
I always configure splits (sub-terminals) in groups of two and use one single-key for "next", so I can flip between two sub-terminals with the same keybinding. With qterminal I need to use one keybinding for the "left" and one keybiding for the "right" sub-terminal.

Describe the solution you'd like
Add the functionality with a configurable keybind so I can cycle through sub-terminals

Describe eventual alternatives you've considered
One has to use directional navigation which is impractical, worth noting most other terminal support something like this.

Context

This is the only thing keeping me from switching to qterminal.