feat: Adicionar aviso de IVA em todos os preços

�� IVA NÃO INCLUÍDO - Avisos adicionados

📍 LOCAIS ATUALIZADOS:

1. Pricing Page (/pricing)
   - Aviso "+ IVA" abaixo do preço principal
   - Texto destacado em amarelo

2. Profile Page (/profile)
   - Seção de assinatura com "(IVA não incluído)"

3. Billing Page (/billing)
   - Plano atual com aviso de IVA

🌍 i18n - 3 Idiomas:

pt-BR:
- plusVat: "+ IVA"
- vatNotIncluded: "(IVA não incluído)"
- billedAnnually: "...€{{price}} + IVA"

ES:
- plusVat: "+ IVA"
- vatNotIncluded: "(IVA no incluido)"
- billedAnnually: "...€{{price}} + IVA"

EN:
- plusVat: "+ VAT"
- vatNotIncluded: "(VAT not included)"
- billedAnnually: "...€{{price}} + VAT"

🎨 VISUAL:
- Texto em amarelo (text-warning)
- Destaque com fw-semibold
- Posicionamento consistente

✅ Cliente agora vê claramente que IVA será adicionado

frontend/src/i18n/locales/en.json

@@ -2208,7 +2208,9 @@
     "free": "Free",
     "month": "month",
     "year": "year",
-    "billedAnnually": "Billed annually €{{price}}",
+    "plusVat": "+ VAT",
+    "vatNotIncluded": "(VAT not included)",
+    "billedAnnually": "Billed annually €{{price}} + VAT",
     "save": "Save {{percent}}%",
     "trialDays": "{{days}}-day free trial",
     "trial": "trial",

frontend/src/i18n/locales/es.json

@@ -2200,7 +2200,9 @@
     "free": "Gratis",
     "month": "mes",
     "year": "año",
-    "billedAnnually": "Facturado anualmente €{{price}}",
+    "plusVat": "+ IVA",
+    "vatNotIncluded": "(IVA no incluido)",
+    "billedAnnually": "Facturado anualmente €{{price}} + IVA",
     "save": "Ahorra {{percent}}%",
     "trialDays": "{{days}} días de prueba gratis",
     "trial": "de prueba",

frontend/src/i18n/locales/pt-BR.json

@@ -2218,7 +2218,9 @@
     "free": "Grátis",
     "month": "mês",
     "year": "ano",
-    "billedAnnually": "Cobrado anualmente €{{price}}",
+    "plusVat": "+ IVA",
+    "vatNotIncluded": "(IVA não incluído)",
+    "billedAnnually": "Cobrado anualmente €{{price}} + IVA",
     "save": "Economize {{percent}}%",
     "trialDays": "{{days}} dias de teste grátis",
     "trial": "de teste",

frontend/src/pages/Billing.jsx

@@ -208,6 +208,9 @@ export default function Billing() {
                   <span className="text-muted">
                     /{plan.billing_period === 'annual' ? t('billing.year') : t('billing.month')}
                   </span>
+                  <span className="text-warning fw-semibold ms-2">
+                    ({t('pricing.vatNotIncluded') || '+ IVA'})
+                  </span>
                 </p>
               )}
             </div>

frontend/src/pages/Pricing.jsx

@@ -135,8 +135,11 @@ export default function Pricing() {
                         €{plan.monthly_price.toFixed(2)}
                         <span className="fs-6 fw-normal text-muted">/{t('pricing.month')}</span>
                       </div>
+                      <div className="text-warning small fw-semibold">
+                        {t('pricing.plusVat')}
+                      </div>
                       {plan.billing_period === 'annual' && (
-                        <div className="text-muted small">
+                        <div className="text-muted small mt-1">
                           {t('pricing.billedAnnually', { price: plan.price })}
                         </div>
                       )}

frontend/src/pages/Profile.jsx

@@ -611,8 +611,9 @@ export default function Profile() {
                             {subscriptionData.plan.name}
                             <span className="badge bg-success ms-2">{t('common.active') || 'Ativo'}</span>
                           </h6>
-                          <p className="text-muted mb-2" style={{ fontSize: '14px' }}>
+                          <p className="text-muted mb-1" style={{ fontSize: '14px' }}>
                             {subscriptionData.plan.formatted_price} / {subscriptionData.plan.billing_period === 'monthly' ? t('common.month') || 'mês' : t('common.year') || 'ano'}
+                            <span className="text-warning fw-semibold ms-2">({t('pricing.vatNotIncluded') || '+ IVA'})</span>
                           </p>
                           {subscriptionData.subscription?.current_period_end && (
                             <p className="text-muted mb-0" style={{ fontSize: '13px' }}>