AP-5442: Implement SCA firm permissions

[colinbruce]

What

Link to story

This implements a special_children_act role in the permissions table
It then ensures that, once the feature flag is enabled, only a provider with the role set is able to search for SCA proceedings

Checklist

Before you ask people to review this PR:

• Tests and rubocop should be passing: bundle exec rake
• Github should not be reporting conflicts; you should have recently run git rebase main.
• The standards in the Git Workflow document on Confluence should be followed
• There should be no unnecessary whitespace changes. These make diffs harder to read and conflicts more likely.
• The PR description should say what you changed and why, with a link to the JIRA story.
• You should have looked at the diff against main and ensured that nothing unexpected is included in your changes.
• You should have checked that the commit messages say why the change was made.

[jsugarman]

LGTM

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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