Creates a file record and returns a presigned URL for uploading the file content to S3.
file_id.Name of the file to upload
File record created successfully.
Unique identifier for the file
Always "file"
Name of the file
Initial status is "pending"
Presigned S3 URL for uploading the file content (PUT request)
ISO 8601 timestamp when the upload URL expires
ISO 8601 timestamp when the file record was created