Backend REST API Consistency Restructure

[SeriousHorncat]

Checklist before requesting a review

• I have performed a self-review of my code.
• My code follows the style guidelines enforced by static analysis tools.
• If it is a core feature, I have added thorough tests.
• My changes generate no new warnings.
• New and existing unit tests pass locally with my changes.
• Will this be part of a product update? If yes, please write one phrase about this update.

Pull Request Details

Wrike Ticket - Revise API Routes according to proposal to better define resources and sub-resources and their relationships

Changes made:

• Restructured the REST API to consistently establish relationships with a resource and its sub-resources.
• Delete methods no longer have a 'body' within them
• Backend unit testing completely relies on fixtures from the backend fixtures; Removed dependency of the initial database seed
• Each analysis fixture used for unit testing in the backend is collected to build the collections; this way it is easier to find the correct analysis the unit test is using
• System tests rely on fixtures within the system tests for images and documents

Updates affected the full stack from unit to system-level testing.

To Review:

• Static Analysis by Reviewer
• Run Unit Tests for front and backend locally
• Run E2E System Tests locally
• Review the new organization with the API Docs Rosalution API Docs Local Deployment
• All GitHub Actions checks have passed

Screenshots

[fatimarabab]

All tests passed - frontend unit tests, backend unit and integration tests, system tests.

[fatimarabab]

Looks great! Excited to get this in! :)

[JmScherer]

System Tests

Frontend Unit Tests

Backend Unit Tests

Backend Integration Tests

[JmScherer]

[JmScherer]

Nothing sticks out and everything runs as it should. This PR was massive!