feat(tui,coding-agent): add shell-style keybindings alt+b, alt+f, ctrl+d

- Add alt+b/alt+f as alternative bindings for cursorWordLeft/cursorWordRight
- Add ctrl+d as alternative binding for deleteCharForward
- Fix ctrl+d in custom editor to perform delete when text is present
  (previously it was always consumed, even with non-empty input)

Closes #1043

Co-authored-by: Jason Ish <ish@unx.ca>

packages/tui/src/keybindings.ts

@@ -68,15 +68,15 @@ export const DEFAULT_EDITOR_KEYBINDINGS: Required<EditorKeybindingsConfig> = {
 	cursorDown: "down",
 	cursorLeft: "left",
 	cursorRight: "right",
-	cursorWordLeft: ["alt+left", "ctrl+left"],
-	cursorWordRight: ["alt+right", "ctrl+right"],
+	cursorWordLeft: ["alt+left", "ctrl+left", "alt+b"],
+	cursorWordRight: ["alt+right", "ctrl+right", "alt+f"],
 	cursorLineStart: ["home", "ctrl+a"],
 	cursorLineEnd: ["end", "ctrl+e"],
 	pageUp: "pageUp",
 	pageDown: "pageDown",
 	// Deletion
 	deleteCharBackward: "backspace",
-	deleteCharForward: "delete",
+	deleteCharForward: ["delete", "ctrl+d"],
 	deleteWordBackward: ["ctrl+w", "alt+backspace"],
 	deleteWordForward: ["alt+d", "alt+delete"],
 	deleteToLineStart: "ctrl+u",