feat: allow 2 users to complete a questionary concurrently

[TCMeldrum]

Description

This PR introduces functionality to allow 2 users to complete a questionary concurrently.

Motivation and Context

The change is required to prevent conflicts and data loss when two users edit a proposal at the same time. The system will prompt the second user to merge their answers, thus ensuring data integrity and a smoother user experience.

Changes

1. A new column 'last_edited' has been added to the 'answers' table to track the last edit timestamp.
2. The 'QuestionaryDataSource' has been updated to include 'last_edited' in the answer records.
3. The 'AnswerTopic' mutation has been extended to check for conflicts based on the 'last_edited' timestamp before updating an answer. If a conflict is detected, it returns an error message prompting the user to merge their answers.

How Has This Been Tested?

Fixes Jira Issue

https://jira.ess.eu//browse/

Depends On

Tests included/Docs Updated?

• I have added tests to cover my changes.
• All relevant doc has been updated

[zacharyjhankin]

I think there is an edge case that was missed. Where if person 1 edits and saves the proposal while person 2 is in the review phase. Then person 2 presses the back button, they load the inital answers into the form (before person 1 edited it). Then they do their update and it effectively deletes person 1s edits from existence.

Screencast.From.2026-08-24.09-17-13.mp4

I would not say that this bug necessarily is a reason to reject this PR though.

[zacharyjhankin]

I might vote to use radio-buttons instead of checkboxes when selecting which answer to use. Because checkboxes imply you could select both. (which makes sense for text to append)

radio buttons you usually can only select 1

[zacharyjhankin]

I think there might be another bug when you use the instrumentPicker question as the place for conflicts because the wrong callId is passed to the answer renderer?

[0] {"error":"{"userMessage":"Can not answer topic because the answers have been edited by another user",{"questionId":"instrument_picker_question","value":"{\"value\":{\"instrumentId\":\"1\",\"timeRequested\":\"0\"}}"}],"topicId":10,"isPartialSave":false,"editStartTime":"2026-08-24T08:45:25.454Z"}}}}"}
[0] [2026-08-24T08:45:31.190Z] INFO - GraphQL request received
[0] {"client":"UOP frontend","client_type":"frontend","operation":"getInstrumentsByIdsMinimal","operation_Type":"query"}
[0] [2026-08-24T08:45:31.191Z] INFO - GraphQL request received
[0] {"client":"UOP frontend","client_type":"frontend","operation":"getCallByAnswerId","operation_Type":"query"}
[0] [2026-08-24T08:45:31.192Z] INFO - GraphQL request received
[0] {"client":"UOP frontend","client_type":"frontend","operation":"getInstrumentsByIdsMinimal","operation_Type":"query"}
[0] [2026-08-24T08:45:31.195Z] INFO - GraphQL request received
[0] {"client":"UOP frontend","client_type":"frontend","operation":"getCallByAnswerId","operation_Type":"query"}
[0] [2026-08-24T08:45:31.198Z] ERROR - GraphQL response contained error(s)
[0] {"errors":[{"message":"Call not found for answerId: 101","locations":[{"line":2,"column":3}],"path":["getCallByAnswerId"]}],"context":{"requestUserId":6,"request":{"query":"query getCallByAnswerId($answerId: Int!) {\n getCallByAnswerId(answerId: $answerId) {\n allocationTimeUnit\n }\n}","operationName":"getCallByAnswerId","variables":{"answerId":101},"http":{"method":"POST","headers":{},"search":"","body":{"query":"query getCallByAnswerId($answerId: Int!) {\n getCallByAnswerId(answerId: $answerId) {\n allocationTimeUnit\n }\n}","variables":{"answerId":101},"operationName":"getCallByAnswerId"}}}}}

I can't get this error to show unless it comes at the same time as the new popup of the answer conflicts. I think callId became a field that you need to pass to the question now.

[zacharyjhankin]

"Your current answer:"
"Your current answer"
maybe

[zacharyjhankin]

Currently saved answer

[zacharyjhankin]

"A user has updated"

[zacharyjhankin]

I think the abstract can still be deleted when two users edit it simultaniously. Maybe it it is worth getting that to be included in the same validation if possible? I imagine that might even be the most edited/conflicted field ?

[TCMeldrum]

@zacharyjhankin Thanks very much for the review!

I think its not just if one user is in the review phase, its part of a larger bug as when you navigate to a topic it doesn’t re-fetch the answers as I thought it did so a user 2 users editing different topic might cause conflicts. Thanks for finding it!

For the instrument picker question I could not replicate it my set up will look into further.

For the proposal abstract I was going to try and fix it in another PR as it is on a different mutation to the rest of the answers but I'll try and deal with here as well.