feat: Add CSV sink in new streaming engine

[coastalwhite]

Mostly a copy of #19431.

[orlp]

Looking at crates/polars-io/src/csv/write/write_impl.rs there is internal parallelism with rayon here. Ideally that happens inside the node with parallel input before linearizing.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 78 lines in your changes missing coverage. Please review.

Project coverage is 79.92%. Comparing base (425e251) to head (0e8bcad).
Report is 85 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/polars-stream/src/nodes/io_sinks/csv.rs	0.00%	78 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #19441      +/-   ##
==========================================
- Coverage   79.96%   79.92%   -0.04%     
==========================================
  Files        1534     1535       +1     
  Lines      211030   211108      +78     
  Branches     2444     2444              
==========================================
- Hits       168750   168734      -16     
- Misses      41725    41819      +94     
  Partials      555      555              

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