feat(expr): add _pg_expandarray function

[wangrunji0408]

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What's changed and what's your intention?

Added a new table function _pg_expandarray.

fix #12204

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
• I have added fuzzing tests or opened an issue to track them. (Optional, recommended for new SQL features Sqlsmith: Sql feature generation #7934).
• My PR contains breaking changes. (If it deprecates some features, please create a tracking issue to remove them in the future).
• All checks passed in ./risedev check (or alias, ./risedev c)
• My PR changes performance-critical code. (Please run macro/micro-benchmarks and show the results.)

• My PR contains critical fixes that are necessary to be merged into the latest release. (Please check out the details)

Documentation

• My PR needs documentation updates. (Please use the Release note section below to summarize the impact on users)

Release note

Add a new table function:

_pg_expandarray(array anyarray) → record(x anyelement, n int)

Returns the input array as a set of rows with an index.

[wangrunji0408]

Is there a way to ignore the lint?

expr.proto:250:5:Enum value name "_PG_EXPANDARRAY" should be UPPER_SNAKE_CASE, such as "PG_EXPANDARRAY".

[TennyZhuang]

LGTM
It seems that buf lint does not support fine-grained ignoring. The only way is to name it as PG_EXPANDARRAY and rewrite it in the frontend.

[TennyZhuang]

I found this.

https://buf.build/docs/lint/overview#ignore_only

[codecov]

Codecov Report

Merging #12448 (7d1b6fd) into main (5a2ee63) will decrease coverage by 0.01%.
Report is 17 commits behind head on main.
The diff coverage is 42.85%.

@@            Coverage Diff             @@
##             main   #12448      +/-   ##
==========================================
- Coverage   69.64%   69.63%   -0.01%     
==========================================
  Files        1422     1423       +1     
  Lines      235747   235782      +35     
==========================================
+ Hits       164192   164198       +6     
- Misses      71555    71584      +29     

Flag	Coverage Δ
rust	69.63% <42.85%> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files Changed	Coverage Δ
src/expr/macro/src/lib.rs	91.48% <ø> (ø)
src/expr/src/table_function/mod.rs	70.19% <ø> (ø)
src/frontend/src/binder/expr/function.rs	78.34% <0.00%> (-0.70%)	⬇️
src/expr/src/table_function/pg_expandarray.rs	28.57% <28.57%> (ø)
src/expr/macro/src/gen.rs	97.02% <100.00%> (+0.03%)	⬆️

... and 4 files with indirect coverage changes

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[TennyZhuang]

Will https://buf.build/docs/lint/overview#allow_comment_ignores be better?