feat: sync pricing currency with selected language

Switch to MAD when Arabic is selected, EUR for French, USD for English.
Currency still overridable via the manual toggle.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/marketplace/src/app/(public)/pricing/PricingClient.tsx

@@ -1,6 +1,6 @@
 'use client'
 
-import { useState } from 'react'
+import { useEffect, useState } from 'react'
 import Link from 'next/link'
 import { useMarketplacePreferences } from '@/components/MarketplaceShell'
 import { resolveBrowserAppUrl } from '@/lib/appUrls'
@@ -10,6 +10,8 @@ type Billing = 'monthly' | 'annual'
 
 const SYMBOL: Record<Currency, string> = { MAD: 'MAD', USD: '$', EUR: '€' }
 
+const LANGUAGE_CURRENCY: Record<string, Currency> = { ar: 'MAD', fr: 'EUR', en: 'USD' }
+
 const PRICES: Record<string, Record<Currency, { monthly: number; annual: number }>> = {
   STARTER: {
     MAD: { monthly: 299,  annual: 2990  },
@@ -123,8 +125,12 @@ function annualSavingsPct(plan: string, currency: Currency): number {
 export default function PricingClient() {
   const { language } = useMarketplacePreferences()
   const dict = copy[language]
-  const [currency, setCurrency] = useState<Currency>('MAD')
+  const [currency, setCurrency] = useState<Currency>(() => LANGUAGE_CURRENCY[language] ?? 'MAD')
   const [billing, setBilling] = useState<Billing>('monthly')
+
+  useEffect(() => {
+    setCurrency(LANGUAGE_CURRENCY[language] ?? 'MAD')
+  }, [language])
   const dashboardUrl = resolveBrowserAppUrl(process.env.NEXT_PUBLIC_DASHBOARD_URL ?? 'http://localhost:3000/dashboard')
 
   const savings = annualSavingsPct('STARTER', currency)