history improvements: backspace passthrough, hint rearranged

ambient.d.ts

@@ -350,6 +350,8 @@ interface Utils {
 	complete_do(this: Optional<ICommand, 'Tag'>): undefined
 	replace_me(_match: string, _offset: number, whole: string): string
 	scroll(): true
+	get scrolled(): boolean
+	rescroll(func: (_: undefined) => unknown): true
 }
 
 interface Complete {
@@ -448,7 +450,7 @@ interface InputHistory {
 	/**
 	 * Specific key handlers.
 	 */
-	key: Record<string, (textarea: HTMLTextAreaElement) => true>
+	key: Record<string, (event: KeyboardEvent, textarea: HTMLTextAreaElement) => true>
 
 	/**
 	 * Set or unset the readonly mode on the input.
@@ -463,7 +465,7 @@ interface InputHistory {
 	/**
 	 * Exit the history mode and proc the key event.
 	 */
-	exit(textarea: HTMLTextAreaElement, key: KeyboardEvent['key']): true
+	exit(textarea: HTMLTextAreaElement, e: KeyboardEvent): true
 }
 
 // FIXME spread around readonly where appropriate