Adds deleteWordForward action bound to Alt+D, which deletes from cursor
to the end of the current word and saves to kill ring for later yanking.
Consecutive forward kills append to the same kill ring entry.
Add kill ring functionality with:
- Ctrl+W/U/K save deleted text to kill ring
- Ctrl+Y yanks (pastes) most recent deletion
- Alt+Y cycles through kill ring (after Ctrl+Y)
- Consecutive deletions accumulate into single entry
In legacy terminal mode (non-Kitty protocol), Alt+key is sent as ESC
followed by the key character. This was only supported for specific keys
(space, backspace, arrows) but not for regular letters.
Add support for Alt+letter sequences to enable keybindings like Alt+Y.