Add exam grading result DTOs

src/main/java/com/example/questionbank/web/rest/dto/AnswerResult.java

@@ -0,0 +1,13 @@
+package com.example.questionbank.web.rest.dto;
+
+import com.example.questionbank.domain.enumeration.OptionKey;
+
+public record AnswerResult(
+    Long questionId,
+    String questionText,
+    OptionKey selectedOption,
+    String selectedContent,
+    boolean correct,
+    int awardedPoints,
+    String explanation
+) {}

src/main/java/com/example/questionbank/web/rest/dto/ExamResult.java

@@ -0,0 +1,6 @@
+package com.example.questionbank.web.rest.dto;
+
+import java.time.Instant;
+import java.util.List;
+
+public record ExamResult(Long attemptId, int totalScore, Instant submittedAt, List<AnswerResult> answers) {}