fix: follow undergraduate login links and capture live history URLs

mobile/test/school/undergraduate_page_probe_test.dart

@@ -6,6 +6,51 @@ import 'package:hepan_everyday/features/school/undergraduate/page_probe.dart';
 
 void main() {
   final uri = Uri.parse('https://eams.uestc.edu.cn/eams/');
+  test(
+    'legacy HTTP continuation upgrade is limited to the exact school system',
+    () {
+      expect(
+        UndergraduateNavigationPolicy.secureIdentityRedirect(
+          Uri.parse(
+            'http://eams.uestc.edu.cn/eams/home.action?login=1&next=%2Feams%2F#continue',
+          ),
+        ).toString(),
+        'https://eams.uestc.edu.cn/eams/home.action?login=1&next=%2Feams%2F#continue',
+      );
+      for (final address in [
+        'http://eams.uestc.edu.cn.attacker.test/eams/home.action',
+        'http://user@eams.uestc.edu.cn/eams/home.action',
+        'http://eams.uestc.edu.cn:8080/eams/home.action',
+        'http://eams.uestc.edu.cn/other/action',
+      ]) {
+        expect(
+          UndergraduateNavigationPolicy.secureIdentityRedirect(
+            Uri.parse(address),
+          ),
+          isNull,
+        );
+      }
+    },
+  );
+  test(
+    'decoder still requires captured URL to match the live document URL',
+    () {
+      expect(
+        () => UndergraduatePageEvidence.decode({
+          'topUrl': 'https://eams.uestc.edu.cn/eams/courseTableForStd.action?semester.id=523',
+          'authenticated': true,
+          'pages': [
+            {
+              'kind': 'timetable',
+              'url': 'https://eams.uestc.edu.cn/eams/courseTableForStd.action?semester.id=523',
+              'html': 'table',
+            },
+          ],
+        }, uri),
+        throwsFormatException,
+      );
+    },
+  );
   test(
     'navigation and capture distinguish official data from authentication',
     () {