[adoption_osp_deploy] Allow overriding scenario stack CLI args

[imatza-rh]

Summary

• Add cifmw_adoption_osp_deploy_stack_args_remove and cifmw_adoption_osp_deploy_stack_args_add variables to the adoption_osp_deploy role
• These allow callers to modify the TripleO overcloud deploy CLI arguments inherited from the DPA scenario file

Problem

TripleO CLI arguments like --libvirt-type generate internal heat environments that are applied after all user-provided -e files. This means cifmw_adoption_osp_deploy_overcloud_extra_args (which creates internal-configuration.yaml as the last -e file) cannot override them.

For shiftstack adoption jobs, we need --libvirt-type kvm instead of --libvirt-type qemu (nested virt requires KVM), but the existing override mechanism has no effect.

Solution

Use Ansible's reject('in', ...) filter to remove unwanted args (preserving order) and append replacements:

# In Zuul job vars:
cifmw_adoption_osp_deploy_stack_args_remove:
  - '--libvirt-type qemu'
cifmw_adoption_osp_deploy_stack_args_add:
  - '--libvirt-type kvm'

The defaults are empty lists, so this is fully backwards compatible — existing jobs produce byte-identical output.

Note: An earlier implementation used difference(), but Ansible's difference filter uses sets internally and scrambles arg order. The reject('in', ...) filter preserves the original ordering from the DPA scenario file.

Changes

File	Change
defaults/main.yml	New defaults: _stack_args_remove: [], _stack_args_add: []
tasks/deploy_overcloud.yml	Core logic: reject('in', remove) | list + add | join(' ')
tasks/validate_scenario.yml	Input validation: both vars must be lists (not string/mapping)
molecule/default/converge.yml	6 test scenarios exercising the Jinja2 expression
molecule/default/verify.yml	Assertions: content, order preservation, no-op, append position
README.md	Documents both new parameters

Test plan

• Molecule tests pass (6 scenarios: default, remove, add, replace, multi-remove, no-op)
• ci-framework-jobs MR !2964 consumes this via Depends-On
• Verify shiftstack adoption deploy-osp produces --libvirt-type kvm in the overcloud deploy command
• All 8 existing adoption jobs unaffected (defaults produce identical output)

Assisted-By: Claude Code

[openshift-ci]

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