feat(transfer): persist reusable transfer tasks

apps/desktop/src/components/transfer/taskLoadTracker.ts

@@ -0,0 +1,21 @@
+export interface TaskLoadToken {
+  generation: number;
+  taskId: string;
+}
+
+export function createTaskLoadTracker() {
+  let generation = 0;
+
+  return {
+    begin(taskId: string): TaskLoadToken {
+      generation += 1;
+      return { generation, taskId };
+    },
+    cancel() {
+      generation += 1;
+    },
+    isCurrent(token: TaskLoadToken, activeTaskId: string | null) {
+      return token.generation === generation && token.taskId === activeTaskId;
+    },
+  };
+}