perf(modal): unify cancellable frontend modal flows

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/Identity/ApplicationService.php

@@ -189,7 +189,6 @@ final class ApplicationService {
             'result_code' => (string) $application['provider_result_code'],
             'message' => (string) $application['provider_result_summary'],
             'redirect_url' => esc_url_raw((string) ($application['redirect_url'] ?? '')),
-            'qr_payload' => sanitize_text_field((string) ($application['qr_payload'] ?? '')),
             'expires_at' => (string) ($application['expires_at'] ?? ''),
             'created_at' => (string) $application['created_at'],
             'poll_interval' => (int) SettingsRuntime::get()['poll_interval_seconds'],