v1.5.6 of kterm

kterm is a fast and fully-featured terminal emulator for Flutter applications, with support for mobile and desktop platforms. Changelog excerpt: ### Bug Fixes - **Kitty KeyUp encoding only when `reportAllKeysAsEscape`is enabled**: Previously, pressing a modifier (e.g. Cmd+V) and releasing it sent a Kitty KeyUp sequence even without `reportAllKeysAsEscape`, causing cursor jumping in the remote…