feat(settings): allow Danger Zone for any owner regardless of company count

Removes three layered gates that kept the Danger Zone completely hidden unless the current user had more than one company:

1. SettingsLayoutView's showDangerZone computed no longer checks companies.length > 1 — just is_owner. 2. DangerZoneView drops the v-if that wrapped the delete button with the same check. 3. Admin\\CompaniesController::destroy() drops the companies_count <= 1 early-return that was enforcing the rule server-side (translation key You_cannot_delete_all_companies was inline in the controller, not in lang files or tests, so nothing else needs cleanup).

The reasoning behind the old gate was that a user with zero companies would be stranded. That's a misread of how the app degrades: /admin/no-company already exists as a graceful fallback view, and the user can create a fresh company from there to recover. Hiding the entire delete flow just to avoid that fallback UX was overkill — the name-confirmation modal already prevents accidental deletion.

app/Http/Controllers/Admin/CompaniesController.php

@@ -97,10 +97,6 @@ class CompaniesController extends Controller
             return respondJson('company_name_must_match_with_given_name', 'Company name must match with given name');
         }
 
-        if ($user->loadCount('companies')->companies_count <= 1) {
-            return respondJson('You_cannot_delete_all_companies', 'You cannot delete all companies');
-        }
-
         $this->companyService->delete($company, $user);
 
         return response()->json([