fix(adminfront): fix ReferenceErrors and null checks in UI components

- Import and initialize 'navigate' in TenantUsersPage and TenantAdminsAndOwnersTab.
- Use optional chaining for 'user.id' in UserDetailPage to prevent runtime errors during initial load.

adminfront/src/features/users/UserDetailPage.tsx

@@ -1078,7 +1078,7 @@ function UserDetailPage() {
                         id="role"
                         className="flex h-11 w-full rounded-md border border-input bg-background px-3 py-2 text-sm shadow-sm transition-colors focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-primary disabled:opacity-50"
                         {...register("role")}
-                        disabled={profile?.role !== "super_admin" || profile?.id === user.id}
+                        disabled={profile?.role !== "super_admin" || profile?.id === user?.id}
                       >
                         <option value="super_admin">
                           {t("ui.admin.role.super_admin", "시스템 관리자")}