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/lib/agency.ts

@@ -10,6 +10,9 @@ export const INTEGRATION_PROVIDERS = [
   { id: 'klaviyo', label: 'Klaviyo', group: 'email' },
   { id: 'mailchimp', label: 'Mailchimp', group: 'email' },
   { id: 'google_drive', label: 'Google Drive', group: 'files' },
+  { id: 'wordpress', label: 'WordPress', group: 'cms' },
+  { id: 'prestashop', label: 'PrestaShop', group: 'cms' },
+  { id: 'shopify', label: 'Shopify', group: 'cms' },
 ] as const;
 
 export type IntegrationProviderId =