feat(helpdesk): rework handover tabs and assign flow

Tabs: replace open/closed with active (draft+in_progress+under_review)
and done (completed+archived) — records now appear in the correct tab

Create wizard assign mode: redirect to list with flash message after
assigning instead of opening edit page

i18n: add In progress / Done tab labels and wizard strings (de + en)

Nikita Soldatov note: user does not exist in DB — needs to be created
via admin user management

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

modules/helpdesk/lib/Module/Helpdesk/Repository/HandoverRepository.php

@@ -89,9 +89,9 @@ class HandoverRepository
         if ($status !== '' && $status !== 'all') {
             $where[] = 'h.status = ?';
             $params[] = $status;
-        } elseif ($view === 'open') {
-            $where[] = "h.status NOT IN ('completed', 'archived')";
-        } elseif ($view === 'closed') {
+        } elseif ($view === 'active') {
+            $where[] = "h.status IN ('draft', 'in_progress', 'under_review')";
+        } elseif ($view === 'done') {
             $where[] = "h.status IN ('completed', 'archived')";
         }