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

closes #7

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

composables/downloads.ts

@@ -0,0 +1,27 @@
+import { listen } from "@tauri-apps/api/event";
+
+export type QueueState = {
+  queue: Array<{ id: string; status: string; progress: number | null }>;
+  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;
+});