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The GitHub Actions job "Direct Backport Push" on texera.git/main has succeeded.
Run started by GitHub user github-merge-queue[bot] (triggered by github-merge-queue[bot]).

Head commit for run:
d9c50f229e0b4f01170c1c61da37cbcc1fff6d6f / Tanishq Gandhi <56...@users.noreply.github.com>
fix(k8s): make the computing-unit prepuller follow texeraImages.pullPolicy (#8973)

### What changes were proposed in this PR?

The computing-unit prepull DaemonSet hardcoded imagePullPolicy: Always,
so on clusters that load images into the nodes (kind, minikube,
air-gapped) setting texeraImages.pullPolicy to IfNotPresent or Never had
no effect on it. Its init container still tried to pull from the
registry and failed.

It now reads {{ .Values.texeraImages.pullPolicy }}, like the Jupyter
prepull DaemonSet and every other template that pulls a Texera image.
texeraImages.pullPolicy defaults to Always, so default installs render
exactly as before.

Rendered with helm template, before:
```
pullPolicy=Always        | CU prepuller: Always | Jupyter prepuller: Always
pullPolicy=IfNotPresent  | CU prepuller: Always | Jupyter prepuller: IfNotPresent
pullPolicy=Never         | CU prepuller: Always | Jupyter prepuller: Never
```
After:
```
pullPolicy=Always        | CU prepuller: Always       | Jupyter prepuller: Always
pullPolicy=IfNotPresent  | CU prepuller: IfNotPresent | Jupyter prepuller: IfNotPresent
pullPolicy=Never         | CU prepuller: Never        | Jupyter prepuller: Never
```

### Any related issues, documentation, discussions?
Closes #8972

### How was this PR tested?

Rendered the DaemonSet with helm template under each
texeraImages.pullPolicy value, before and after (output above), and with
the default values, which still give Always.
bin/k8s/tests/test_helm_values.sh passes.

### Was this PR authored or co-authored using generative AI tooling?
Generated-by: Claude Code (Claude Opus 5.5)

Co-authored-by: Meng Wang <me...@uci.edu>

Report URL: https://github.com/apache/texera/actions/runs/38822755887

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