Changing the variant of the cozystack.cozystack-platform Package on a
running cluster changes bundles.system.variant and can re-render the
cozystack.networking Package with another variant. The operator then
deletes every HelmRelease of that Package the new variant does not
install, so isp-full -> isp-hosted removes Cilium and Kube-OVN and the
cluster loses its CNI; isp-full -> isp-slim removes Kube-OVN.

The platform render now looks up the live Package and fails when its
variant differs from the one about to be rendered, unless
networking.acknowledgeVariantChange names the new variant. The
acknowledgement is a variant name rather than a boolean so that a value
left behind after one switch does not cover a later one. The check is
inert where lookup returns nothing (helm template, client-side dry-run,
first install) and skipped when cozystack.networking is in
bundles.disabledPackages, since the platform then does not render it.

A live variant set by hand, such as cilium-kilo, is pointed at
bundles.disabledPackages rather than at the acknowledgement: the
acknowledged render would write the bundle's variant over it.

Assisted-by: LLM
Signed-off-by: Aleksei Sviridkin <[email protected]>
(cherry picked from commit 1245b32)