Default opened_at in upsert

X-Lovable-Edit-ID: edt-1c27884e-3833-4317-be65-fa310119b791
Co-authored-by: renee-png <262607627+renee-png@users.noreply.github.com>

src/routes/settings.import.tsx

@@ -284,6 +284,11 @@ const IMPORTERS: ImporterConfig[] = [
         // in batched upserts where Postgrest sends the column union.
         r.status = "intake";
       }
+      // Default opened_at to today when missing — avoids NULL violations
+      // in batched upserts where Postgrest sends the column union.
+      if (!r.opened_at) {
+        r.opened_at = new Date().toISOString().slice(0, 10);
+      }
       // Normalise billing method
       if (r.billing_method) {
         const bm = String(r.billing_method).toLowerCase();