add docs for aggregation function datasketches_hll_union_agg

[nooneuse]

Please See: apache/doris#63143
Documentation for the datasketches_hll_union_agg aggregate function.

Versions

• dev
• 4.x
• 3.x
• 2.1 or older (not covered by version/language sync gate)

Languages

• Chinese
• English
• Japanese candidate translation needed

Docs Checklist

• Checked by AI
• Test Cases Built
• Updated required version and language counterparts, or explained why not
• If only one language changed, confirmed whether source/translation counterparts need sync

[zclllyybb]

@nooneuse please also add for 4.x version with label to remind it's supported since 4.1.2. and resolve the conflicts. thx~

[nooneuse]

@nooneuse please also add for 4.x version with label to remind it's supported since 4.1.2. and resolve the conflicts. thx~

Hello @zclllyybb @linrrzqqq ! I have added the documentation for the 4.x version and included a note in the relevant docs: "supported since 4.1.2". Also I have resolved the conflicts. Please review it when you have time, thank you!

[nooneuse]

Hi @linrrzqqq @zclllyybb ! I have fixed the issue in sidebars.ts. Please review it when you have time. Thanks!

[nooneuse]

Emm...Why some check cancelled but failed?

[nooneuse]

Hi @linrrzqqq @zclllyybb ! I have fixed the issue in sidebars.ts. Please review it when you have time. Thanks!