Uplift of #29093 (squashed) to beta

Author: brave-builds

ios/brave-ios/Sources/Playlist/PlaylistDownloadManager.swift

@@ -413,7 +413,7 @@ private class PlaylistHLSDownloadManager: NSObject, AVAssetDownloadDelegate {
   func urlSession(
     _ session: URLSession,
     assetDownloadTask: AVAssetDownloadTask,
-    didFinishDownloadingTo location: URL
+    willDownloadTo location: URL
   ) {
     pendingDownloadTasks[assetDownloadTask] = location
   }
@@ -531,7 +531,8 @@ private class PlaylistHLSDownloadManager: NSObject, AVAssetDownloadDelegate {
     // so we must synchonously move the file to a temporary directory first before processing it
     // on a different thread since the Task will execute after this method returns
     let assetUrl = FileManager.default.temporaryDirectory
-      .appending(component: "\(asset.id)-\(temporaryUrl.lastPathComponent)")
+      .appending(component: asset.id).appendingPathExtension(temporaryUrl.pathExtension)
+
     try? FileManager.default.moveItem(at: temporaryUrl, to: assetUrl)
 
     @Sendable func cleanupAndFailDownload(location: URL?, error: Error) async {
@@ -920,7 +921,7 @@ private class PlaylistFileDownloadManager: NSObject, URLSessionDownloadDelegate
       // so we must synchonously move the file to a temporary directory first before processing it
       // on a different thread since the Task will execute after this method returns
       let temporaryLocation = FileManager.default.temporaryDirectory
-        .appending(component: location.lastPathComponent)
+        .appending(component: asset.id).appendingPathExtension(location.pathExtension)
       try? FileManager.default.moveItem(at: location, to: temporaryLocation)
       Task {
         // Couldn't determine file type so we assume mp4 which is the most widely used container.