Odoo 19: Replace routing_map-based endpoint_route_handler registration tests

[jeremi]

Background

endpoint_route_handler tests were skipped on Odoo 19 because routing_map() no longer reflects dynamically registered controllers in the same way.

Skipped tests

• test_as_tool_register_single_controller
• test_as_tool_register_controllers
• test_as_tool_register_controllers_dynamic_route

Goal

Replace these with Odoo 19-compatible assertions that still verify dynamic route registration/update behavior.

Acceptance criteria

• Remove skip decorators from the three tests (or replace with equivalent active tests).
• Assertions validate route registration/update behavior under Odoo 19 runtime semantics.
• Tests are stable in CI.

References

• endpoint_route_handler/tests/test_endpoint.py