feat(gui): add ask-user question composer

packages/ui/user-interaction/README.md

@@ -17,7 +17,7 @@ Abstract user-interaction seam. It owns `ctx.userInteraction`, the service a mod
 - `UserInteractionProvider` — UI implementation with `ask(request)`.
 - `UserInteractionError` — `HarnessError` subclass with codes such as `EMPTY_QUESTIONS`, `NO_PROVIDER`, `DUPLICATE_PROVIDER`, and `ASK_ABORTED`.
 
-When an answer includes `custom`, `selected` is empty; custom text is an override rather than a supplement to selected choices.
+When an answer includes `custom`, `selected` is empty; custom text is an override rather than a supplement to selected choices. A UI may preserve a skipped item as `{ id, selected: [] }`, keeping the existing answer shape while retaining other answers in the batch.
 
 ## Role
 

packages/ui/user-interaction/src/types.ts

@@ -31,7 +31,7 @@ export interface AskUserQuestionItem {
 export interface AskUserQuestionAnswerItem {
   /** The answered question id. */
   id: string
-  /** Selected option labels. Empty when the answer is purely custom text. */
+  /** Selected option labels. Empty for custom or unanswered choices. */
   selected: string[]
   /** Optional free-text "Other" answer. */
   custom?: string