Enforce login on tenant domains in OrganizationMiddleware and add tests

[oumafreddy]

Motivation

• Ensure tenant (per-organization) sites require authentication before processing requests to prevent anonymous access to tenant domains.
• Clarify middleware processing order by enforcing authentication early for tenant requests.

Description

• Updated apps/core/middleware.py OrganizationMiddleware to return a redirect to the login page when a request.tenant is present and the request.user is not authenticated, moving the authentication enforcement earlier in the request flow.
• Preserved existing tenant-access controls for authenticated users, including logout and an error message when a user lacks access to the current tenant.
• Added tests in apps/users/tests/test_organization_middleware.py to cover anonymous access on the public site, required login for tenant sites, and allowed access for authenticated users belonging to the tenant.

Testing

• Ran the new middleware tests with python manage.py test apps.users.tests.test_organization_middleware and all tests passed.

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Codex Task