fix(adminfront): fix tenant slug display and metadata save issue in user detail page

- Fix 'System Global' displaying by replacing user.tenantSlug with user.companyCode returned by backend
- Prevent primary tenant from being unlinked when saving 'Tenant Profile' tab by ensuring userAffiliatedTenants always includes the primary tenant, preventing react-hook-form from clearing the tenantSlug value.

adminfront/src/features/users/UserDetailPage.tsx

@@ -391,7 +391,7 @@ function UserDetailPage() {
         phone: user.phone || "",
         role: user.role,
         status: user.status,
-        tenantSlug: user.tenantSlug || "",
+        tenantSlug: user.companyCode || "",
         department: user.department || "",
         position: user.position || "",
         jobTitle: user.jobTitle || "",
@@ -484,8 +484,15 @@ function UserDetailPage() {
     );
   }
 
-  const userAffiliatedTenants =
-    user.joinedTenants || (user.tenant ? [user.tenant] : []);
+  const userAffiliatedTenants = React.useMemo(() => {
+    const joined = user.joinedTenants || [];
+    const primary = user.tenant;
+    const all = [...joined];
+    if (primary && !joined.some((t) => t.id === primary.id)) {
+      all.unshift(primary);
+    }
+    return all;
+  }, [user.joinedTenants, user.tenant]);
 
   return (
     <div className="space-y-6">
@@ -525,7 +532,7 @@ function UserDetailPage() {
               >
                 <Building2 size={12} className="mr-1.5" />
                 {user.tenant?.name ||
-                  user.tenantSlug ||
+                  user.companyCode ||
                   t("ui.admin.users.detail.form.tenant_global", "시스템 전역")}
               </Badge>
               <Badge