fix(auth): a member behind the register's clock says the password changed

When a member's clock ran more than its allowance behind the register's,
the session after a reset was refused as unavailable (the re-review's tenth
finding), after the register had already reset the account and ended every
session, and the app read it as "this instance has no password sign-in".
It now has a refusal of its own (passwordChanged): the app says the password
was changed and to sign in again with the new one.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

packages/halkyon_app/test/password/widget/password_texts_test.dart

@@ -63,5 +63,12 @@ void main() {
       ),
       contains('signed out'),
     );
+    expect(
+      passwordProblemText(
+        context,
+        const PasswordFailed(PasswordProblem.passwordChanged),
+      ),
+      allOf(contains('was changed'), contains('Sign in again')),
+    );
   });
 }