feat: add support for one-off recording schedules with start and end datetime

templates/roster.html

@@ -772,6 +772,8 @@
 
     // Handle Add Unit form submission
     document.getElementById('addUnitForm').addEventListener('htmx:afterRequest', function(event) {
+        // Only handle the form's own POST request, not child HTMX requests (e.g. project picker search)
+        if (event.detail.elt !== this) return;
         if (event.detail.successful) {
             closeAddUnitModal();
             refreshDeviceList();