Describe the bug

What went wrong?

1. When you upload a new document as a participatory text, you have a preview to check that everything is in order, but if it's not, if there is an error, you don't have the option to go back and reload it again.
   This means that in order to repeat the operation you have to create a new component of proposals, not being able to delete the first one. And you can end up having 'n' proposal components depending on the errors you make when uploading the file.
2. Also: you can't edit the document title once is published, and this can be also a problem.

What did you expect to happen?

1. I expected to have an option to reset and reload the file as long as it hasn't been published yet.
2. I expected to be able to change the title of the PT without having to upload any file.

Additional context
https://meta.decidim.org/processes/bug-report/f/210/proposals/13772