fix(e2e): use dedicated reset user instead of admin in password-reset test

Introduces a separate reset@familyarchive.local / reset123 seed account
(e2e profile only) so the password-reset flow test never touches the
shared admin credentials.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/src/main/java/org/raddatz/familienarchiv/user/UserDataInitializer.java

@@ -102,6 +102,21 @@ public class UserDataInitializer {
                 log.info("E2E seed: 'reader'-Testbenutzer erstellt.");
             }
 
+            if (userRepository.findByEmail("reset@familyarchive.local").isEmpty()) {
+                log.info("E2E seed: Erstelle 'reset'-Testbenutzer...");
+                UserGroup leserGroup = groupRepository.findByName("Leser").orElseGet(() ->
+                        groupRepository.save(UserGroup.builder()
+                                .name("Leser")
+                                .permissions(Set.of("READ_ALL"))
+                                .build()));
+                userRepository.save(AppUser.builder()
+                        .email("reset@familyarchive.local")
+                        .password(passwordEncoder.encode("reset123"))
+                        .groups(Set.of(leserGroup))
+                        .build());
+                log.info("E2E seed: 'reset'-Testbenutzer erstellt.");
+            }
+
             if (personRepo.count() > 0) {
                 log.info("E2E seed: Personendaten bereits vorhanden, überspringe Dokument-Seed.");
                 return;