fix: cherry-pick several udf fixes

[wangrunji0408]

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What's changed and what's your intention?

resolve #13846 and cherry-pick other recent udf fixes:

• fix(udf): fix decimal values #11839
• fix(udf): fix index-out-of-bound error when string or string list is large. #13781
• fix(udf): fix memory leak in Java UDF #13789
• fix(udf): avoid panic on invalid output and fix decimal output scale lost #13828

[TennyZhuang]

It'll be better if the PR will not be squashed. (But the option is closed in the admin page).

[xxchan]

It'll be better if the PR will not be squashed. (But the option is closed in the admin page).

I think we can now enable merge commits for PRs, since main requires merge queue (which is configured to use squash merge). 🤔