Options for how uploads are stored and linked to spreadsheet

Nextcloud (please complete the following information):

• Nextcloud-Version: 32.0.4
• Forms-Version: 5.2.4

Is your feature request related to a problem? Please describe.
In Forms, files that are uploaded when submitting a form are now stored in folders, one folder per submission. Folders are automatically numbered continously.
This can creates problems:

1. If submissions are deleted, and thereby also their uploads-folders, other folder numbers are not updated. Thus, folder names do not follow spreadsheet row number any more. E.g. I deleted the first two submission of a series, and uploads-folders are now only numbered from 3. If this happens more times, it will be very troublesome to link submissions with their uploads.
2. The separate folders pr submission makes it very tedious to combine all submitted files into one folder or document, as we need for our accounts.

Describe the solution you'd like

1. a unique identifier / link between each submission in the spreadsheet and associated uploads(-folder) (has also been suggested by someone else in this forum)
2. an option to write this identifier to the file name(s) of the uploaded files (or replace the file name)
3. an option to select if uploads should be stored in separate folders per submission or in one common folder

Describe alternatives you've considered
I have used Google Forms before, where all submitted files are linked to entries in the spreadsheet

Additional context
We, a Danish nature organization, have just recently moved to Nextcloud, and will use Forms to allow users to submit request for refunds. They will fill in a form and submit associated receipts, and this will be used to keep track of expenses and for the annual accounts, including associated receipt as a documentation

No files, tests, or entry points are named in the issue. Start by locating the existing upload-storage and spreadsheet-association entry points in Nextcloud Forms, then define how identifiers, shared or per-submission folders, and deleted submissions should behave; done means the selected storage options preserve an unambiguous link between each submission and its uploads.