Synchronise 2026.1 with upstream - #236

Build succeeded.
https://zuul.stackhpc.com/t/stackhpc/buildset/f9a8e06108884e0890e0f8f448775bee

✔️ openstack-tox-cover SUCCESS in 1h 36m 36s
✔️ openstack-tox-pep8 SUCCESS in 9m 44s
✔️ openstack-tox-docs SUCCESS in 13m 23s
✔️ build-openstack-releasenotes SUCCESS in 14s
❌ nova-tox-validate-backport FAILURE in 7m 14s (non-voting)
✔️ nova-tox-functional-py310 SUCCESS in 46m 33s
✔️ nova-tox-functional-py313 SUCCESS in 40m 09s
✔️ nova-tox-py312-threading SUCCESS in 24m 19s