fix(uploads): set kb presignedEndpoint fallback; race-safe blob HEAD

Author: waleedlatif1

apps/sim/app/workspace/[workspaceId]/knowledge/hooks/use-knowledge-upload.ts

@@ -257,6 +257,7 @@ export function useKnowledgeUpload(options: UseKnowledgeUploadOptions = {}) {
           file,
           workspaceId: options.workspaceId,
           context: 'knowledge-base',
+          presignedEndpoint: '/api/files/presigned',
           presignedOverride: presigned,
           onProgress,
         })

apps/sim/lib/uploads/providers/blob/client.ts

@@ -341,14 +341,19 @@ export async function headBlobObject(
   const containerClient = blobServiceClient.getContainerClient(containerName)
   const blockBlobClient = containerClient.getBlockBlobClient(key)
 
-  if (!(await blockBlobClient.exists())) {
-    return null
-  }
-
-  const properties = await blockBlobClient.getProperties()
-  return {
-    size: properties.contentLength ?? 0,
-    contentType: properties.contentType,
+  try {
+    const properties = await blockBlobClient.getProperties()
+    return {
+      size: properties.contentLength ?? 0,
+      contentType: properties.contentType,
+    }
+  } catch (err) {
+    const status = (err as { statusCode?: number }).statusCode
+    const code = (err as { code?: string }).code
+    if (status === 404 || code === 'BlobNotFound') {
+      return null
+    }
+    throw err
   }
 }