[Backport release-1.6] feat(kubevirt): expose migration configuration through platform values - #4402

Replace negative Chainsaw assertions with deletion watches, keeping the
two-minute timeout and the preceding Bound assertions for both PVCs.

Chainsaw 0.2.15 can abort polling on an API read error and report its
previous "resource matches expectation" instead. The failed cozystack#4402 run
ended this check after 4.5 seconds, not its two-minute budget.

Verified with Chainsaw 0.2.15 and kubectl 1.33.13 against a loopback API:
delayed deletion, already absent, a read failure on the old polling path,
and watch reconnect succeed; retained PVCs and forbidden reads fail.
Chainsaw lint passes. The original CI API error was not preserved; a
full E2E rerun is still needed.

Signed-off-by: Yan Bondarenko <[email protected]>

… CRD wait is cancelled (#4475)

Backport of #3742 to `release-1.6`.

`TestWaitForCRDsEstablished_timeout` fails `Unit & controller tests` on
this branch at random, last time on #4402: `error should mention stuck
CRD name, got: context cancelled while waiting for CRDs to be
established: context deadline exceeded`. `WaitForCRDsEstablished` here
still has two cancellation exits with different messages, and when the
deadline and a ticker tick are ready together the select picks one of
them at random. I ran the timeout test as 16 concurrent processes to get
the timing jitter CI has: 3 failures out of 160 runs on the current
branch, 0 out of 320 with this change.

Cherry-picked clean with `-x`.

### Testing

- stress run above, plus `make unit-tests` and `make test-controllers`
green, POSIX sh sweep clean.

```release-note
fix(manifestutil): a CRD wait cut short by a cancelled context now reports one error naming the CRD it was waiting on, where before the name was present or missing depending on which of two exits the scheduler happened to pick
```

This reopens a fork pull request from a branch in this repository so its
CI can run. The commit is the one from #4481 by @yankawai, unchanged. On
release-1.6 the pull-request CI pushes the images it builds, and a run
from a fork has no registry credentials, so #4481 could never get past
the build jobs to e2e. The description below is the author's.

## What this PR does

Wait for both ZooKeeper PVCs to disappear after Kafka deletion. Negative
assertions can stop on an API read error before their timeout; deletion
watches wait for the resource to be removed. The existing Bound and
KafkaTopic checks are unchanged.

Carries the test-only change from c92828c in #4339, which was not
included in #4402. This targets `release-1.6`; the Kafka suite on `main`
uses KRaft without ZooKeeper.

Validated with Chainsaw 0.2.15: delayed deletion, an already absent PVC,
an interrupted watch, and the read-error fixture pass. A retained PVC
and forbidden access fail. The full Kafka E2E run remains for CI.

### Screenshots

Not applicable.

### Downstream repositories

- [x] No downstream repository is affected by this change
- [ ] [cozystack/website](https://github.com/cozystack/website) -
follow-up:
- [ ]
[cozystack/terraform-provider-cozystack](https://github.com/cozystack/terraform-provider-cozystack)
- follow-up:
- [ ]
[cozystack/ansible-cozystack](https://github.com/cozystack/ansible-cozystack)
- follow-up:
- [ ] [cozystack/ccp](https://github.com/cozystack/ccp) - follow-up:
- [ ] [cozystack/talm](https://github.com/cozystack/talm) - follow-up:
- [ ] [cozystack/cozyhr](https://github.com/cozystack/cozyhr) -
follow-up:
- [ ] [cozystack/cozy-proxy](https://github.com/cozystack/cozy-proxy) -
follow-up:
- [ ]
[cozystack/cozystack-telemetry-server](https://github.com/cozystack/cozystack-telemetry-server)
- follow-up:
- [ ]
[cozystack/external-apps-example](https://github.com/cozystack/external-apps-example)
- follow-up:
- [ ] [cozystack/examples](https://github.com/cozystack/examples) -
follow-up:

### Release note

```release-note
NONE
```

cozystack/cozystack#4402 backports the kubevirt.migrations platform value
to the 1.6 line, and the v1.6 reference had no KubeVirt section at all.
This adds the migrations row and its example from the next page, with a
line saying the value is available since v1.6.4, because earlier 1.6
releases ignore it. The disabledFeatureGates row stays out, as that value
is not on the 1.6 line.

Signed-off-by: Yan Bondarenko <[email protected]>

## What this PR does

Adds a KubeVirt section with the `kubevirt.migrations` row, its example
and the note on bandwidth units to the v1.6 platform-package reference.
It documents the value that cozystack/cozystack#4402 backported to
`release-1.6`. That backport first ships in v1.6.4, so the section says
the value is available since Cozystack v1.6.4 and that earlier 1.6
releases ignore it. The `kubevirt.disabledFeatureGates` row from `next`
stays out because that value is not on the 1.6 line. The row and the
example are the ones #697 added to `next`.

Checks run for this change.

- `bash hack/check-i18n.sh check` passed with 29 translation keys and 20
tracked translated pages.
- `git diff origin/main...HEAD --check` passed, and the PR changes one
reference file.
- Hugo was not built locally.

### Screenshots

Not applicable, reference documentation only.

### Downstream repositories

- [x] No downstream repository is affected by this change
- [ ] [cozystack/website](https://github.com/cozystack/website) -
follow-up:
- [ ]
[cozystack/terraform-provider-cozystack](https://github.com/cozystack/terraform-provider-cozystack)
- follow-up:
- [ ]
[cozystack/ansible-cozystack](https://github.com/cozystack/ansible-cozystack)
- follow-up:
- [ ] [cozystack/ccp](https://github.com/cozystack/ccp) - follow-up:
- [ ] [cozystack/talm](https://github.com/cozystack/talm) - follow-up:
- [ ] [cozystack/cozyhr](https://github.com/cozystack/cozyhr) -
follow-up:
- [ ] [cozystack/cozy-proxy](https://github.com/cozystack/cozy-proxy) -
follow-up:
- [ ]
[cozystack/cozystack-telemetry-server](https://github.com/cozystack/cozystack-telemetry-server)
- follow-up:
- [ ]
[cozystack/external-apps-example](https://github.com/cozystack/external-apps-example)
- follow-up:
- [ ] [cozystack/examples](https://github.com/cozystack/examples) -
follow-up:
- [ ] [cozystack/community](https://github.com/cozystack/community) -
follow-up:

This reference-only change does not alter any downstream API, schema,
build tooling, installer setting or runtime behavior.

### Release note

```release-note
docs(platform-package): Document kubevirt.migrations, available since v1.6.4, on the v1.6 platform values reference.
```