fix(helpdesk): handle missing session in EffectiveHelpdeskSettingsService

Scheduler jobs run without an active session, causing SessionStore::all()
to fail. Wrap the call in try-catch to fall back to global config (tenant
ID 0) when no session is available.

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

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

@@ -188,7 +188,13 @@ class EffectiveHelpdeskSettingsService
 
     private function resolveCurrentTenantId(): int
     {
-        $session = $this->sessionStore->all();
+        try {
+            $session = $this->sessionStore->all();
+        } catch (\Throwable) {
+            // No active session (e.g. scheduler context) → fall back to global config
+            return 0;
+        }
+
         $tenant = $session['current_tenant'] ?? null;
         if (!is_array($tenant)) {
             return 0;