Field specific traits

[bellerbrock]

Description

Provide a summary of your changes including motivation and context.
If these changes fix a bug or resolves a feature request, be sure to link to that issue.

Adds trait editor activity access from field detail page, with any visibility changes tracked on the field-level using a study_id jsonb column in the observation_variables table.

closes #1014

Type of change

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• CHANGE (fix or feature that would cause existing functionality to not work as expected)
• FEATURE (non-breaking change which adds functionality)
• BUGFIX (non-breaking change which fixes an issue)
• ENHANCEMENT (non-breaking change which improves existing functionality)
• NONE (if none of the other choices apply. Example, tooling, build system, CI, docs, etc.)

Checklist:

• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have updated relevant documentation

Changelog entry

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[bellerbrock]

Not a finished product yet, opening as a draft PR as a place for testing/feedback

The main remaining question is if trait visibility should be field-specific everywhere now, or just when accessing the trait and collect activities from the field detail fragment? So far the changes are implemented with the second strategy in mind - preservsing the field-independent visibility info when accessing the trait and collect activities from the config activity. But I'm worried that both approaches side-by-side will be confusing, and it would be a lot simpler to completely switch over.

If we don't completely switch over I will still need to go through and update additional places that check trait visibility (summary, datagrid, export) to determine in which contexts they should apply the field-specific trait visibility or the general trait visibility.

I also still need to set field-specific visibility for traits imported by Brapi sync.