refactor: Update download history logic to exclude cancelled tasks

backend/src/services/downloadManager.ts

@@ -11,6 +11,7 @@ interface DownloadTask {
   cancelFn?: () => void;
   sourceUrl?: string;
   type?: string;
+  cancelled?: boolean;
 }
 
 class DownloadManager {
@@ -141,6 +142,7 @@ class DownloadManager {
     const task = this.activeTasks.get(id);
     if (task) {
       console.log(`Cancelling active download: ${task.title} (${id})`);
+      task.cancelled = true;
       
       // Call the cancel function if available
       if (task.cancelFn) {
@@ -269,6 +271,7 @@ class DownloadManager {
       }
 
       // Add to history
+      if (!task.cancelled) {
         storageService.addDownloadHistoryItem({
           id: task.id,
           title: finalTitle || task.title,
@@ -279,6 +282,7 @@ class DownloadManager {
           sourceUrl: videoData.sourceUrl || task.sourceUrl,
           author: videoData.author,
         });
+      }
 
       // Trigger Cloud Upload (Async, don't await to block queue processing?)
       // Actually, we might want to await it if we want to ensure it's done before resolving,
@@ -298,6 +302,7 @@ class DownloadManager {
       storageService.removeActiveDownload(task.id);
 
       // Add to history
+      if (!task.cancelled) {
         storageService.addDownloadHistoryItem({
           id: task.id,
           title: task.title,
@@ -306,6 +311,7 @@ class DownloadManager {
           error: error instanceof Error ? error.message : String(error),
           sourceUrl: task.sourceUrl,
         });
+      }
 
       task.reject(error);
     } finally {