added guardian login with views for their assigned childs

lib/api/marianumconnect/queries/absence/absence_prefill.dart

@@ -2,9 +2,14 @@ import '../../marianumconnect_query.dart';
 import 'absence_prefill_response.dart';
 
 /// GETs the absence-report form prefill (`absence/prefill`, bearer-auth).
+/// Guardians pass the [childId] the report is for; the identity then comes
+/// from that child.
 class AbsencePrefill extends MarianumConnectQuery {
   AbsencePrefill({super.dio});
 
-  Future<AbsencePrefillResponse> run() =>
-      getObject('absence/prefill', AbsencePrefillResponse.fromJson);
+  Future<AbsencePrefillResponse> run({String? childId}) => getObject(
+    'absence/prefill',
+    AbsencePrefillResponse.fromJson,
+    queryParameters: {'childId': ?childId},
+  );
 }

lib/api/marianumconnect/queries/absence/absence_submit.dart

@@ -3,7 +3,8 @@ import '../../marianumconnect_query.dart';
 /// Submits an absence report (`POST absence`, bearer-auth, `source=mobile`).
 /// Empty identity fields are backfilled from LDAP server-side; validation
 /// (all fields required, class must exist, no past start date, end >= start)
-/// also runs server-side and mirrors the client checks.
+/// also runs server-side and mirrors the client checks. For guardians the
+/// server takes name and class from the child given by [childId].
 class AbsenceSubmit extends MarianumConnectQuery {
   AbsenceSubmit({super.dio});
 
@@ -15,6 +16,7 @@ class AbsenceSubmit extends MarianumConnectQuery {
     required DateTime absentUntil,
     required String phone,
     required String note,
+    String? childId,
   }) => guard(() async {
     await dio.post<void>(
       endpoint('absence'),
@@ -26,6 +28,7 @@ class AbsenceSubmit extends MarianumConnectQuery {
         'absentUntil': isoDate(absentUntil),
         'phone': phone,
         'note': note,
+        'childId': ?childId,
       },
     );
   });