feat(helpdesk): add multi-tenant BC connection settings with risk radar refinements

Introduce per-tenant override for helpdesk BC connection config.
New table helpdesk_tenant_settings stores tenant-specific credentials
with encrypted secrets (AES-256-GCM). EffectiveHelpdeskSettingsService
resolves global vs tenant config per request. Settings UI extended with
tenant override tab, toggle, and dual editing mode.

All runtime consumers (OData, SOAP, OAuth) read through the new
resolver. Token cache flushed on any config change. Default behavior
unchanged — tenants use global config until override explicitly enabled.

Also includes risk radar UI refinements: Stripe-style card redesign
with accent borders and score pills, removal of redundant KPI tiles
and search, and filtering of zero-score entries.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

modules/helpdesk/lib/Module/Helpdesk/Service/DebitorSearchService.php

@@ -11,7 +11,7 @@ class DebitorSearchService
 
     public function __construct(
         private readonly BcODataGateway $bcODataGateway,
-        private readonly HelpdeskSettingsGateway $settingsGateway
+        private readonly EffectiveHelpdeskSettingsService $settingsGateway
     ) {
     }