perf(expr): support writer-style #[function] for bytea, jsonb and array type

[wangrunji0408]

Is your feature request related to a problem? Please describe.

For functions that return varchar, we now support writer-style signatures, allowing functions to write results directly to the array buffer.

#[function("trim(varchar) -> varchar")]
pub fn trim(s: &str, writer: &mut impl Write) {
    writer.write_str(s.trim()).unwrap();
}

But this is not supported for functions that return bytea, jsonb or arrays. They have to return owned Box<[u8]>, JsonbVal or ListVal right now, which causes unnecessary overhead of malloc and memcpy.

Describe the solution you'd like

Similar to varchar, we can support a writer of type impl std::io::Write for bytea:

#[function("concat_op(bytea, bytea) -> bytea")]
pub fn concat_op(left: &[u8], right: &[u8], writer: &mut impl std::io::Write) {
    writer.write(left).unwrap();
    writer.write(right).unwrap();
}

and type JsonbBuilder(jsonbb::Builder) for jsonb:

#[function("subtract(jsonb, varchar) -> jsonb")]
fn jsonb_remove(v: JsonbRef<'_>, key: &str, builder: &mut JsonbBuilder) -> Result<()> {
    ...
}

Describe alternatives you've considered

No response

Additional context

No response

[github-actions]

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