fix(frontend): remove locale-dependent routing and migrate to centralized locale-aware router

- Replaced `next/navigation` with `@/lib/i18n/routing` across components, pages, and tests.
- Removed redundant `locale` props from `ProjectWizard` and related pages.
- Updated navigation to exclude explicit `locale` in paths.
- Refactored tests to use mocks from `next-intl/navigation`.

frontend/src/app/[locale]/(authenticated)/projects/page.tsx

@@ -10,7 +10,7 @@
 'use client';
 
 import { useState, useCallback, useMemo } from 'react';
-import { useRouter } from 'next/navigation';
+import { useRouter } from '@/lib/i18n/routing';
 import { toast } from 'sonner';
 import { Plus } from 'lucide-react';
 import { Button } from '@/components/ui/button';