[bengbengbalabalabeng]

Purpose of the pull request

As title

What's changed?

Checklist

• I have read the Contributor Guide.
• I have written the necessary doc or comment.
• I have added the necessary unit tests and all cases have passed.

[GOODBOY008]

Thanks for the update! Verified against the codebase:

• HeadBuilder.forSimple(...) returns List<List<String>>, matching the head(List) overload, and produces the same single-level head as the previous Arrays.asList(Collections.singletonList(...)) construction.
• The builder -> builder.column(...) lambda resolves to AbstractParameterBuilder#head(Consumer<HeadBuilder>); each column("Main Title", "Group A", "Name") call expands to the same per-column path as the old inner lists, so the merge-strategy example keeps its exact semantics.
• HeadBuilder has been available since 2.1.0-incubating (#943), so the docs won't advertise an unreleased API.
• EN/zh pages stay in sync, and no stale List<List<String>> head construction is left behind.

One minor follow-up (non-blocking): in website/docs/sheet/write/head.md the sentence right below the merge-strategy example still says "Each inner list is one column..." — with the new builder.column(...) style it would read better as "Each column(...) call defines one column, listing its title from the top level down."