fix: odkaz Otvorit v Brevo vedie priamo na upravu kampane (uloha 17)

Namiesto napevno zadaneho zoznamu kampani (404) sa odkaz sklada z ID
kampane: app.brevo.com/marketing-campaign/edit/{id}.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/app/api/brevo/export/route.ts

@@ -1,4 +1,5 @@
 import { NextRequest, NextResponse } from 'next/server';
+import { getBrevoCampaignUrl } from '@/lib/brevo';
 
 export async function POST(req: NextRequest) {
   try {
@@ -63,7 +64,7 @@ export async function POST(req: NextRequest) {
           success: true,
           updated: true,
           campaignId: Number(existingCampaignId),
-          brevoUrl: 'https://app.brevo.com/campaigns/listing',
+          brevoUrl: getBrevoCampaignUrl(existingCampaignId),
           brevoListingUrl: 'https://app.brevo.com/campaigns/listing',
           message: 'Kampaň bola úspešne aktualizovaná v Brevo!'
         });
@@ -113,7 +114,7 @@ export async function POST(req: NextRequest) {
       success: true,
       updated: false,
       campaignId: data.id,
-      brevoUrl: 'https://app.brevo.com/campaigns/listing',
+      brevoUrl: getBrevoCampaignUrl(data.id),
       brevoListingUrl: 'https://app.brevo.com/campaigns/listing',
       message: 'Kampaň bola úspešne vytvorená v Brevo!'
     });