feat: Add Int128 IO support for csv & ipc

[lukemanley]

No description provided.

[codecov]

Codecov Report

Attention: Patch coverage is 71.42857% with 6 lines in your changes missing coverage. Please review.

Project coverage is 79.04%. Comparing base (1ebd039) to head (ada490c).
Report is 11 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/polars-arrow/src/io/ipc/write/schema.rs	0.00%	2 Missing ⚠️
crates/polars-io/src/csv/read/buffer.rs	86.66%	2 Missing ⚠️
crates/polars-arrow/src/io/ipc/read/schema.rs	50.00%	1 Missing ⚠️
...s/polars-io/src/csv/write/write_impl/serializer.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff            @@
##             main   #20535    +/-   ##
========================================
  Coverage   79.04%   79.04%            
========================================
  Files        1563     1564     +1     
  Lines      220798   220631   -167     
  Branches     2502     2502            
========================================
- Hits       174522   174396   -126     
+ Misses      45702    45661    -41     
  Partials      574      574            

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