Get poll by share token through REST-API

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• I agree to follow Nextcloud's Code of Conduct.

Describe the goal you'd like to achieve

As a user of the REST-API, I would like to be able to get a poll using only a share token.

Currently, it is only possible to access a poll by PollId when using REST-API. When someone gets a public share, they can use the share/{token} endpoint to get the PollId but this doesn't give them the authorization of accessing the poll.

Describe possible solutions

I see two possible implementations :

• Automatically mark the user as involved with a poll when they use the share/{token} endpoint so that they can simply GET poll/{pollId} (or create a dedicated endpoint to get involved with a poll using the share token).
• Create a new endpoint like GET /api/v1.0/poll/{token} which would return a poll.

I would recommend against the second option as it would require more work to create endpoints to let the user access the list of options and to vote to make it entirely functional.

Additional context

No response

Start by reviewing linked pull request #4657 and the existing REST entry points for share/{token} and poll/{pollId}. Confirm the intended authorization flow and whether the share token can support retrieving the poll, its options, and voting; done means the complete token-based REST workflow is functional.