[SPARK-56002][UI] Make SQL plan visualization metrics table sortable

[yaooqinn]

What changes were proposed in this pull request?

Make the metrics table in the SQL plan visualization side panel sortable by clicking column headers.

Changes (JS-only, 1 file):

• Add sortable class to metrics tables built by buildMetricsTable()
• Call sorttable.makeSortable() on dynamically injected tables after innerHTML update
• Add sorttable to the global JS comment

Why are the changes needed?

When inspecting SQL plan nodes with many metrics (e.g., Exchange nodes with 20+ shuffle metrics), sorting by metric name or value helps quickly locate the most relevant metrics.

Does this PR introduce any user-facing change?

Yes — metrics table headers in the SQL plan viz side panel are now clickable to sort.

How was this patch tested?

Manual testing. JS-only change, no Scala changes.

Was this patch authored or co-authored using generative AI tooling?

Yes, co-authored with GitHub Copilot.

[dongjoon-hyun]

Feel free to merge when you feel it's ready.

[dongjoon-hyun]

BTW, for the following one, I also used like you previously.

Yes, co-authored with GitHub Copilot.

However, let's use Generated-By: to be consistent with the Apache Spark Pull Request Template which follows ASF Guidance.

spark/.github/PULL_REQUEST_TEMPLATE

Lines 55 to 56 in 51c3e37

	If generative AI tooling has been used in the process of authoring this patch, please include the
	phrase: 'Generated-by: ' followed by the name of the tool and its version.

https://www.apache.org/legal/generative-tooling.html

There is nothing wrong here. I just want to mention this because of just consistency and we (the Apache Spark PMC member) lead the way in the community.

[yaooqinn]

Thank you @dongjoon-hyun for bringing this out.

For the AI-tooling, what does the version here mean? Does it mean the Copilot Cli, cursor version, or something else similar? You know, such stuffs are evolving pretty fast than traditional software (I update it nearly daily from my side:)). I think the original intention here is to add the LLM model being used, right?

[yaooqinn]

Merged to master
For the PR desc improvement, we can proceed in new PRs