refactor: split ask flow state and view models

src/result-format.ts

@@ -1,4 +1,5 @@
 import { ELABORATED_SUMMARY } from "./constants.ts";
+import { isCustomOnlyAnswer } from "./state/answers.ts";
 import type { AskResult } from "./types.ts";
 
 export function formatResultLines(
@@ -51,10 +52,6 @@ function formatAnswerLine(
 	return `✓ ${questionLabel}: ${answerText}`;
 }
 
-function isCustomOnlyAnswer(answer: AskResult["answers"][string]): boolean {
-	return answer.indices.length === 0 && !!answer.customText;
-}
-
 function formatQuestionNoteLine(
 	questionLabel: string,
 	note: string | undefined,