Add lookahead padding to the plan time axis (#3419)

* Adds 50% padding to the viewBounds.

Co-authored-by: Andrew Henry <akhenry@gmail.com>

src/plugins/plan/Plan.vue

@@ -122,6 +122,11 @@ export default {
         },
         updateViewBounds() {
             this.viewBounds = this.openmct.time.bounds();
+            //Add a 50% padding to the end bounds to look ahead
+            let timespan = (this.viewBounds.end - this.viewBounds.start);
+            let padding = timespan / 2;
+            this.viewBounds.end = this.viewBounds.end + padding;
+
             if (this.timeSystem === undefined) {
                 this.timeSystem = this.openmct.time.timeSystem();
             }