feat(helpdesk): refactor multi-tenant BC settings and risk radar improvements

Restructure helpdesk tenant settings into per-connection config with
improved token handling. Update risk radar data endpoint and UI.
Clean up ImageUploadTrait and update architecture contract tests.

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

modules/helpdesk/web/js/helpdesk-risk-radar.js

@@ -55,7 +55,6 @@ if (container) {
       'open_pressure': d('labelOpenPressure', 'Open pressure'),
       'trend': d('labelTrend', 'Trend'),
       'sla_overdue': d('labelSla', 'SLA overdue'),
-      'resolution': d('labelResolution', 'Resolution time'),
       'inactivity': d('labelInactivity', 'Inactivity'),
     };
     return map[id] || id;