feat(download ui): add speed and time remaining information

closes #7

Co-authored-by: AdenMGB <140392385+AdenMGB@users.noreply.github.com>

desktop/composables/downloads.ts

@@ -5,10 +5,23 @@ export type QueueState = {
   status: string;
 };
 
+export type StatsState = {
+  speed: number; // Bytes per second
+  time: number; // Seconds,
+};
+
 export const useQueueState = () =>
   useState<QueueState>("queue", () => ({ queue: [], status: "Unknown" }));
 
+export const useStatsState = () =>
+  useState<StatsState>("stats", () => ({ speed: 0, time: 0 }));
+
 listen("update_queue", (event) => {
   const queue = useQueueState();
   queue.value = event.payload as QueueState;
 });
+
+listen("update_stats", (event) => {
+  const stats = useStatsState();
+  stats.value = event.payload as StatsState;
+});