Encode generic camera settings in preview URL query

[emontnemery]

Proposed change

Encode generic camera settings in preview URL query instead of storing the setting in flow context

Needs #127382 for tests to pass

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• Dependency upgrade
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• This PR fixes or closes issue: fixes #
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[home-assistant]

Hey there @davet2001, mind taking a look at this pull request as it has been labeled with an integration (generic) you are listed as a code owner for? Thanks!

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[epenet]

Another option would be to keep the user_input internally (eg. self.preview_cam), and then use

        flow = self.hass.config_entries.flow._progress.get(  # noqa: SLF001
            flow_id
        ) or self.hass.config_entries.options._progress.get(flow_id)  # noqa: SLF001
        if not flow:
            _LOGGER.warning("Unknown flow %s while getting image preview", flow_id)
            raise web.HTTPNotFound
        user_input = flow.preview_cam

[davet2001]

@emontnemery now that #127405 is merged, I assume this is no longer needed and can be closed.