fix: address PR review feedback for download cancel/error UI

- Fix transcribe_audio to use whisper-large-v3 mapping (not openai/whisper-large)
- Propagate error field in progress-only fallback path for get_active_tasks
- Use removed return value in cancel endpoint to vary response message
- Add error rollback to handleCancel with toast on failure
- Make isCancelling per-model instead of global
- Fix inverted chevron icons in Problems panel
- Move all clears under lock in clear_all_tasks
- Simplify cancel_download to use dict.pop()

app/src/components/ServerSettings/ModelManagement.tsx

@@ -157,16 +157,30 @@ export function ModelManagement() {
   });
 
   const handleCancel = (modelName: string) => {
-    // Immediately hide the error and suppress downloading state in UI
+    // Snapshot previous state for rollback
+    const prevDismissed = dismissedErrors;
+    const prevLocalErrors = localErrors;
+    const prevDownloadingModel = downloadingModel;
+    const prevDownloadingDisplayName = downloadingDisplayName;
+
+    // Optimistically hide the error and suppress downloading state in UI
     setDismissedErrors((prev) => new Set(prev).add(modelName));
     setLocalErrors((prev) => { const next = new Map(prev); next.delete(modelName); return next; });
-    // Also clear local downloading state if this was our current download
     if (downloadingModel === modelName) {
       setDownloadingModel(null);
       setDownloadingDisplayName(null);
     }
-    // Fire-and-forget the backend cancel, then refetch to sync
-    cancelMutation.mutate(modelName);
+
+    cancelMutation.mutate(modelName, {
+      onError: () => {
+        // Rollback optimistic updates on failure
+        setDismissedErrors(prevDismissed);
+        setLocalErrors(prevLocalErrors);
+        setDownloadingModel(prevDownloadingModel);
+        setDownloadingDisplayName(prevDownloadingDisplayName);
+        toast({ title: 'Cancel failed', description: 'Could not cancel the download task.', variant: 'destructive' });
+      },
+    });
   };
 
   const clearAllMutation = useMutation({
@@ -259,7 +273,7 @@ export function ModelManagement() {
                       }}
                       onCancel={() => handleCancel(model.model_name)}
                       isDownloading={downloadingModel === model.model_name}
-                      isCancelling={cancelMutation.isPending}
+                      isCancelling={cancelMutation.isPending && cancelMutation.variables === model.model_name}
                       isDismissed={dismissedErrors.has(model.model_name)}
                       erroredDownload={erroredDownloads.get(model.model_name)}
                       formatSize={formatSize}
@@ -291,7 +305,7 @@ export function ModelManagement() {
                       }}
                       onCancel={() => handleCancel(model.model_name)}
                       isDownloading={downloadingModel === model.model_name}
-                      isCancelling={cancelMutation.isPending}
+                      isCancelling={cancelMutation.isPending && cancelMutation.variables === model.model_name}
                       isDismissed={dismissedErrors.has(model.model_name)}
                       erroredDownload={erroredDownloads.get(model.model_name)}
                       formatSize={formatSize}
@@ -310,9 +324,9 @@ export function ModelManagement() {
                     className="flex items-center gap-2 hover:text-foreground transition-colors"
                   >
                     {consoleOpen ? (
-                      <ChevronDown className="h-3.5 w-3.5" />
-                    ) : (
                       <ChevronUp className="h-3.5 w-3.5" />
+                    ) : (
+                      <ChevronDown className="h-3.5 w-3.5" />
                     )}
                     <span>Problems</span>
                     <Badge variant="destructive" className="text-[10px] h-4 px-1.5 rounded-full">

backend/main.py

@@ -932,7 +932,11 @@ async def transcribe_audio(
 
         # Check if Whisper model is downloaded (uses default size "base")
         model_size = whisper_model.model_size
-        model_name = f"openai/whisper-{model_size}"
+        # Map model sizes to HF repo IDs (whisper-large needs -v3 suffix)
+        whisper_hf_repos = {
+            "large": "openai/whisper-large-v3",
+        }
+        model_name = whisper_hf_repos.get(model_size, f"openai/whisper-{model_size}")
 
         # Check if model is cached
         from huggingface_hub import constants as hf_constants
@@ -1595,11 +1599,15 @@ async def cancel_model_download(request: models.ModelDownloadRequest):
     removed = task_manager.cancel_download(request.model_name)
 
     # Also clear progress state so the model doesn't show as downloading
+    progress_removed = False
     with progress_manager._lock:
         if request.model_name in progress_manager._progress:
             del progress_manager._progress[request.model_name]
+            progress_removed = True
 
-    return {"message": f"Download task for {request.model_name} cancelled"}
+    if removed or progress_removed:
+        return {"message": f"Download task for {request.model_name} cancelled"}
+    return {"message": f"No active task found for {request.model_name}"}
 
 
 @app.post("/tasks/clear")
@@ -1613,8 +1621,8 @@ async def clear_all_tasks():
 
     with progress_manager._lock:
         progress_manager._progress.clear()
-    progress_manager._last_notify_time.clear()
-    progress_manager._last_notify_progress.clear()
+        progress_manager._last_notify_time.clear()
+        progress_manager._last_notify_progress.clear()
 
     return {"message": "All task state cleared"}
 
@@ -1771,6 +1779,7 @@ async def get_active_tasks():
                 model_name=model_name,
                 status=progress.get("status", "downloading"),
                 started_at=started_at,
+                error=progress.get("error"),
             ))
     
     # Get active generations

backend/utils/tasks.py

@@ -74,10 +74,7 @@ class TaskManager:
     
     def cancel_download(self, model_name: str) -> bool:
         """Cancel/dismiss a download task (removes it from active list)."""
-        if model_name in self._active_downloads:
-            del self._active_downloads[model_name]
-            return True
-        return False
+        return self._active_downloads.pop(model_name, None) is not None
 
     def is_download_active(self, model_name: str) -> bool:
         """Check if a download is active."""