Rewrite rating-service.spec.ts to use TestDatabaseService

[Copilot]

rating-service.spec.ts used hand-rolled mock repos, making tests brittle and disconnected from actual DB behavior. This rewrites it to use TestDatabaseService (in-memory SQLite) in the style of project-service.spec.ts.

Changes

• Replace mock repos with TestDatabaseService: beforeAll bootstraps the DB once; beforeEach calls database.nuke() and re-seeds real entities via TypeORM.
• Real entities in DB: User, Team, Project, Criterion, and Rating are persisted and resolved through actual queries — no more mockResolvedValue chains on fake repo objects.
• ISettingsService remains mocked: it has no DB backing, so MockSettingsService is kept.
• All test cases preserved: permission checks (global disable, missing project, project disallows rating, own-project guard, impersonation), successful upsert, and getRatingResults aggregation.

// Before: manual mock plumbing
mockProjectsRepo.findOneBy.mockResolvedValue(
  Object.assign(new Project(), { ...mockProject, allowRating: false }),
);

// After: real DB state
await projectRepo.update(mockProject.id, { allowRating: false });