Renames `test_models.py` to `models/test_accesslists.py` to improve
test organization and maintainability. This is a structural change
with no modifications to test logic.

Refactor test setup to improve data creation and reusability. Add
detailed fixtures for devices, virtual chassis, clusters,
virtual machines, and prefixes. Update all assignments to reference the
new fixtures for better consistency.

Add test cases to validate AccessList creation and uniqueness for
VirtualChassis and VirtualMachine objects. Extend coverage by ensuring
proper handling of duplicate names and enforcing unique constraints.

Introduces internationalization (i18n) to AccessList models. Updates field
definitions to use `gettext_lazy` for translations and improves model class
field consistency. Includes minor corrections to docstrings and comments.

Move validation to the `save` method to enforce that the assigned
interface's host matches the access list's host before saving.
This replaces validation in the `clean` method for better data integrity
enforcement.

Improve test coverage for ACLInterfaceAssignment validation.
Add tests for valid and invalid direction choices,
duplicate assignments, and missing host assignments to ensure robust
validation logic.

Fixes the unique constraint for ACLInterfaceAssignment by removing the
access_list field from the uniqueness check.
Ensures that only one ACL can be assigned per interface and direction.
Adds validation tests to prevent multiple ACLs from being assigned in
the same direction on the same interface.

Fixes netbox-community#258

Moves ACL rule validation logic from forms to model methods to ensure
consistent enforcement across all usages. This improves maintainability
and eliminates redundant validation code.

Adds comprehensive tests for the ACLStandardRule model. Tests cover rule
creation scenarios, validation constraints, and edge cases,
ensuring thorough model behavior validation.

Fixes netbox-community#47

Introduces comprehensive test cases for the ACLExtendedRule model. These
cover rule creation, validation, and edge cases such as duplicate
indices and invalid combinations of parameters.

Fixes netbox-community#47