feat: add WordPress, PrestaShop and Shopify connection slots

Per-client CMS/ecommerce channels in the agency hub with URL/API
placeholders; live sync can come later.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/app/api/admin/create-client/route.ts

@@ -55,6 +55,9 @@ export async function POST(req: NextRequest) {
           ['klaviyo', 'Klaviyo'],
           ['mailchimp', 'Mailchimp'],
           ['google_drive', 'Google Drive'],
+          ['wordpress', 'WordPress'],
+          ['prestashop', 'PrestaShop'],
+          ['shopify', 'Shopify'],
         ];
         await fetch(`${url}/rest/v1/integrations`, {
           method: 'POST',