EREGCSC-2499 -- Enable subject lookup for non-logged in users

[PhilR8]

Resolves EREGCSC-2499

Description

Allow unauthenticated users visit the Policy Repository and view Public documents.

See Figma comp for design.

This pull request changes:

• Disables Public/Internal document checkboxes and makes "Public" the only checked box.
• Adds login Call to Action in the left sidebar with a log in link if user is not logged in.
• Only public item counts are shown in the Subject Table of Contents.
• Internal items are not returned or displayed from the API until user logs in.

Steps to manually verify this change:

1. Visit experimental deployment and make sure you are NOT logged in.
2. Navigate to the Policy Repository page
3. Make sure the "Documents to Show" checkboxes in the left sidebar are disabled and cannot be toggled via cursor or keyboard navigation.
   • Only "Public" should be checked
4. Under each subject in the Subject Table of Contents, you should only see a count for "public resources"
5. Filtering by subject and search by test string should work as expected but should only display public items.
6. View the API endpoint in your browser and ensure that no internal documents are being returned
7. View the API endpoint with internal documents as the document-type in your browser. You should receive a 403 Forbidden error.
8. Click the "sign in" link on the left side of the page and make sure it takes you to the new custom login screen
   • if you have selected a subject and/or entered a search query, you should see them reflected in the next query param at the new custom login screen
9. Log in using admin (since EUA doesn't work on all experimental deployments)
10. Make sure "Documents to Show" checkboxes are active and can be toggled. Make sure site works as expected.
11. View the API endpoint in your browser and notice that both internal and external documents are now being returned.
12. View the API endpoint with internal documents as the document-type in your browser. You should not receive an error and internal documents should now be returned.

[github-actions]

✨ See the Django Site in action ✨

[github-actions]

✨ See the Django Site in action ✨

[github-actions]

✨ See the Django Site in action ✨

[github-actions]

✨ See the Django Site in action ✨

[github-actions]

✨ See the Django Site in action ✨

[github-actions]

✨ See the Django Site in action ✨

[github-actions]

✨ See the Django Site in action ✨

[peggles2]

LGTM 👍