adds saving and loading history to and from disk

frontend/src/components/TelemetryLine.vue

@@ -30,14 +30,16 @@ const props = defineProps<{
 }>();
 
 const smoothing_distance_x = 5;
+const maximum_minimum_separation_live = 100; // ms
 
 const text_offset = computed(() => 10);
+const min_sep = computed(() => Math.min(props.minimum_separation || 0, maximum_minimum_separation_live));
 
 const { data } = useTelemetry(() => props.data);
 const websocket = inject<ShallowRef<WebsocketHandle>>(WEBSOCKET_SYMBOL)!;
 const value = websocket.value.listen_to_telemetry(
     data,
-    props.minimum_separation,
+    min_sep,
 );
 
 const graph_data = inject<GraphData>(GRAPH_DATA)!;
@@ -84,7 +86,7 @@ watch([value], ([val]) => {
                 x: val_t,
                 y: item_val,
             } as Point;
-            memo.value.insert(new_item);
+            memo.value.insert(new_item, props.minimum_separation);
             if (item_val < min.value) {
                 min.value = item_val;
             }