fix(pdf): restore top-right header to paper id

resources/views/pdf/exam-grading.blade.php

@@ -29,8 +29,8 @@
                 color: #666;
             }
             @top-right {
-                content: "{{ $paperHeaderTitle }}";
-                font-size: 12px;
+                content: "{{ $gradingCode }}";
+                font-size: 17px;
                 font-weight: 600;
                 font-family: "Noto Sans", "Liberation Sans", "Nimbus Sans", sans-serif;
                 letter-spacing: 0;

resources/views/pdf/exam-paper.blade.php

@@ -26,8 +26,8 @@
                 color: #666;
             }
             @top-right {
-                content: "{{ $paperHeaderTitle }}";
-                font-size: 12px;
+                content: "{{ $examCode }}";
+                font-size: 17px;
                 font-weight: 600;
                 font-family: "Noto Sans", "Liberation Sans", "Nimbus Sans", sans-serif;
                 letter-spacing: 0;