update metricsTypes

Using the '/metrics/yyyy_mm_dd' endpoint on the server, there is no longer a discrepancy between server metric data and client metric data.
Also, we can support a variety of GroupingFields now, instead of just 'mode', and the metric values can be objects instead of just numbers.

www/js/metrics/metricsTypes.ts

@@ -1,21 +1,18 @@
-import { LocalDt } from '../types/serverData';
-import { MetricName } from '../types/appConfigTypes';
+import { GroupingField, MetricName } from '../types/appConfigTypes';
 
-type LabelProps = { [k in `label_${string}`]?: number }; // label_<mode>, where <mode> could be anything
-export type DayOfServerMetricData = LabelProps & {
-  ts: number;
-  fmt_time: string;
-  nUsers: number;
-  local_dt: LocalDt;
-};
-
-type ModeProps = { [k in `mode_${string}`]?: number }; // mode_<mode>, where <mode> could be anything
-export type DayOfClientMetricData = ModeProps & {
+// distance, duration, and count use number values in meters, seconds, and count respectively
+// response_count uses object values containing responded and not_responded counts
+type MetricValue = number | { responded?: number; not_responded?: number };
+export type DayOfMetricData = {
   date: string; // yyyy-mm-dd
+  nUsers: number;
+} & {
+  // each key is a value for a specific grouping field
+  // and the value is the respective metric value
+  // e.g. { mode_confirm_bikeshare: 123, survey_TripConfirmSurvey: { responded: 4, not_responded: 5 }
+  [k in `${GroupingField}_${string}`]: MetricValue;
 };
 
-export type DayOfMetricData = DayOfClientMetricData | DayOfServerMetricData;
-
 export type MetricsData = {
   [key in MetricName]: DayOfMetricData[];
 };