fix: Isolate `selected_station()` to prevent unwanted reactive re-evaluation.

server.R

@@ -529,7 +529,7 @@ server <- function(input, output, session) {
         }
 
         # Re-apply highlight if a station is selected
-        st <- selected_station()
+        st <- isolate(selected_station())
         if (!is.null(st)) {
             # Re-gen label for consistency
             period <- get_resolution_period(st, resolution)