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)/agents/[id]/page.tsx

@@ -8,7 +8,8 @@
 'use client';
 
 import { useCallback, useState } from 'react';
-import { useRouter, useParams } from 'next/navigation';
+import { useParams } from 'next/navigation';
+import { useRouter } from '@/lib/i18n/routing';
 import { toast } from 'sonner';
 import { AgentTypeDetail, AgentTypeForm } from '@/components/agents';
 import {

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

@@ -8,7 +8,7 @@
 'use client';
 
 import { useState, useCallback, useMemo } from 'react';
-import { useRouter } from 'next/navigation';
+import { useRouter } from '@/lib/i18n/routing';
 import { toast } from 'sonner';
 import { AgentTypeList } from '@/components/agents';
 import { useAgentTypes } from '@/lib/api/hooks/useAgentTypes';