fix: import unpublished exam rooms and add opt-in school HTML feedback

mobile/lib/features/school/undergraduate/exam_adapter.dart

@@ -102,11 +102,26 @@ class UndergraduateExamAdapter {
       final explicitEmpty = RegExp(r'暂无考试|无考试安排|没有考试|暂无记录|没有符合条件的记录|没有数据|无数据')
           .hasMatch(table.text);
       for (final row in table.querySelectorAll('tr').skip(1)) {
-        final cells = row.children
-            .map((c) => c.text.replaceAll(RegExp(r'\s+'), ' ').trim())
-            .toList();
+        if (explicitEmpty && row.children.length == 1) continue;
+        final cells = <String>[];
+        for (final cell in row.children) {
+          final value = cell.text.replaceAll(RegExp(r'\s+'), ' ').trim();
+          final span = int.tryParse(cell.attributes['colspan'] ?? '1');
+          if ((cell.attributes['rowspan'] ?? '1') != '1') {
+            throw const FormatException('考试记录行合并结构无法识别');
+          }
+          if (span == 1) {
+            cells.add(value);
+          } else if (span == 2 &&
+              cells.length == 4 &&
+              RegExp(r'^[\[【]?考试情况尚未发布[\]】]?$').hasMatch(value)) {
+            // EAMS merges the room and seat columns until it publishes them.
+            cells.addAll([value, '']);
+          } else {
+            throw const FormatException('考试记录列合并结构无法识别');
+          }
+        }
         if (cells.length != 9) {
-          if (explicitEmpty && cells.length == 1) continue;
           throw const FormatException('考试记录字段不完整');
         }
         final rowType = _type(cells[7]);