add callback registration

main.py

@@ -17,6 +17,7 @@ from src.callbacks import (
     register_info_updaters,
     register_map_plot,
     register_timeseries_plot,
+    register_trajdatamissing_response,
 )
 from src.config import DotDict, get_latest_semantic_version_tag
 from src.layout import create
@@ -76,6 +77,7 @@ server = app.server  # for deployment via gunicorn / WSGI server
 
 register_info_updaters(app, varconfig, ap_info)
 register_map_plot(app, data, trajdata, varconfig)
+register_trajdatamissing_response(app)
 register_timeseries_plot(app, data, varconfig)