refactor(leads): export function → V3 action endpoint

Updated download_export__event_exhibit_tracking to call
/v3/action/event_exhibit/{exhibit_id}/tracking_export instead of the
legacy /event/exhibit/{exhibit_id}/tracking/export (V1 path).

Added doc comment listing the expected export columns so the backend
agent has the full field spec when implementing the endpoint.

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

src/lib/ae_events/ae_events__exhibit_tracking.ts

@@ -400,13 +400,25 @@ export async function update_ae_obj__exhibit_tracking({
 }
 
 /**
- * Legacy Export (Special Case - V3 Not Ready)
+ * Export exhibit tracking (leads) to CSV/XLSX.
+ *
+ * V3 Action endpoint: GET /v3/action/event_exhibit/{exhibit_id}/tracking_export
+ * Backend must return the file as a binary response with appropriate Content-Disposition.
+ *
+ * Columns expected in the export (all denormalized onto the tracking record):
+ *   event_exhibit_tracking_id, created_on, updated_on,
+ *   event_exhibit_name,
+ *   event_badge_full_name, event_badge_email, event_badge_professional_title,
+ *   event_badge_affiliations, event_badge_location, event_badge_country,
+ *   external_person_id (captured by), exhibitor_notes,
+ *   responses_json (flattened — one column per custom question code),
+ *   priority, enable, hide
  */
 export async function download_export__event_exhibit_tracking({
     api_cfg,
     exhibit_id,
     file_type = 'CSV',
-    filename = 'exhibit_tracking_export.csv',
+    filename = 'leads_export.csv',
     log_lvl = 0
 }: {
     api_cfg: any;
@@ -415,10 +427,14 @@ export async function download_export__event_exhibit_tracking({
     filename?: string;
     log_lvl?: number;
 }) {
-    const endpoint = `/event/exhibit/${exhibit_id}/tracking/export`;
+    if (log_lvl) {
-    const params = {
+        console.log(`*** download_export__event_exhibit_tracking() *** exhibit_id=${exhibit_id}`);
+    }
+
+    const endpoint = `/v3/action/event_exhibit/${exhibit_id}/tracking_export`;
+    const params: key_val = {
         file_type,
-        return_file: true
+        return_file: 'true'  // V3 convention: string 'true' for bool query flags
     };
 
     return await api.get_object({