feat(flow): support datafusion scalar function

[discord9]

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What's changed and what's your intention?

support datafusion scalar function

Please explain IN DETAIL what the changes are in this PR and why they are needed:

support datafusion scalar function by let datafusion decode substrait proto, and hence build df PhysicalExpr to evaluate function

• added DfScalarFunction which hold both impl of that scalar function and necessary data to ser/de it
• added path in transform module to translate scalar function to df scalar function when no other functions are available

Checklist

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR requires documentation updates.

[codecov]

Codecov Report

Attention: Patch coverage is 71.21771% with 78 lines in your changes missing coverage. Please review.

Project coverage is 84.60%. Comparing base (9473daa) to head (a1ede1a).
Report is 18 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4142      +/-   ##
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- Coverage   85.46%   84.60%   -0.87%     
==========================================
  Files         994     1023      +29     
  Lines      174582   179538    +4956     
==========================================
+ Hits       149204   151894    +2690     
- Misses      25378    27644    +2266     

[zhongzc]

unit tests required

[killme2008]

Again, we need some tests for it.

[killme2008]

LGTM