[hotfix][runtime-web] Restyle Cancel Job/Application action as a danger button

[spuru9]

What is the purpose of the change

The Cancel action on the Job and Application detail pages renders as an oversized 24px blue text link. That's inconsistent with the sibling action links (e.g. "Job Manager Log") and doesn't visually signal that it is a destructive action. This restyles it as a small danger button.

Brief change log

• Render the Cancel Job / Cancel Application action as an ng-zorro nz-button nzDanger nzSize="small" instead of a 24px <a> text link
• Smooth fill-on-hover (danger red, white text) transition
• No behaviour change — the confirmation dialog and cancel logic are untouched

Before:

After:

Verifying this change

Frontend-only styling change, verified manually: open a running job's (and a running application's) detail page and confirm the Cancel action renders as a small red danger button that fills on hover, and that the confirmation dialog and cancellation still work.

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency): no
• The public API, i.e., is any changed class annotated with @Public(Evolving): no
• The serializers: no
• The runtime per-record code paths (performance sensitive): no
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Kubernetes/Yarn, ZooKeeper: no
• The S3 file system connector: no

Documentation

• Does this pull request introduce a new feature? no
• If yes, how is the feature documented? not applicable

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Was generative AI tooling used to co-author this PR?

• Yes (Claude Code)

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CI report:

• 9b5ef16 Azure: SUCCESS

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