Add support for ctrl+tab to the default keyboard translation
This escape matches what e. g. vim and screen recognizes, and seems to be fairly standard.
NB: By default ctrl+tab is mapped to changing tabs in Konsole, so you need to reset that in the shortcut settings for this to have any impact.
This took me embarrassingly long to figure out.
Some references: https://www.staldal.nu/tech/2009/01/10/how-to-use-ctrl-tab-in-gnu-screen/ https://vim.fandom.com/wiki/Alternative_tab_navigation#Firefox_like_navigation