Allow administrators to assign booths before the voting begins

[decabeza]

Current Behavior / Steps to reproduce

1. Create a booth from https://demo.consuldemocracy.org/admin/booths/new
2. Create a poll that starts on a future date from https://demo.consuldemocracy.org/admin/polls/new
3. Assign the booth from https://demo.consuldemocracy.org/admin/polls/2/booth_assignments

Visit the List of active booths https://demo.consuldemocracy.org/admin/booths/available

The list appears empty, making it difficult for administrators to assign shifts for voting, especially in complex elections with many booths and poll officers.

Note: This occurs for both Polls and Polls linked to a Participatory Budget.

Expected Behavior

The list of booths (https://demo.consuldemocracy.org/admin/booths/available) should show all available booths regardless of whether the poll has started or not, so administrators can assign the corresponding shifts and better plan the voting process.

[coslajohn]

A related issue is that an Administrator cannot create a booth if the date assigned to the voting phase is in the past, even if the Voting phase has not yet been selected.

It is very possible that during a PB process online and offline voting might take place at different times and as an administrator I am often asked to create a booth to import paper results.

It would be very helpful if an administrator can create ballots at any time

If you try to create a booth and the date is in the past you are sent to a create poll page which allows you to amend dates, but when you do this it creates a poll, but does not link it to the ballots function of the PB process