refactor(rust): Refactor ArrowSchema to use polars_schema::Schema<D>

[nameexhaustion]

• There is a lot of functionality that works with &[Field], which no longer interops nicely after we change ArrowSchema's repr from Vec<Field> to PlIndexMap<..>, so I've changed them to accept &ArrowSchema instead.

[codecov]

Codecov Report

Attention: Patch coverage is 82.57261% with 42 lines in your changes missing coverage. Please review.

Project coverage is 79.82%. Comparing base (e4746a5) to head (d6d9609).
Report is 33 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/polars-arrow/src/io/ipc/read/file_async.rs	0.00%	12 Missing ⚠️
crates/polars-schema/src/schema.rs	84.78%	7 Missing ⚠️
...rates/polars-arrow/src/io/ipc/read/stream_async.rs	0.00%	5 Missing ⚠️
...es/polars-parquet/src/arrow/read/schema/convert.rs	80.00%	3 Missing ⚠️
crates/polars-stream/src/nodes/parquet_source.rs	0.00%	3 Missing ⚠️
crates/polars-core/src/schema.rs	85.71%	2 Missing ⚠️
crates/polars-io/src/utils/other.rs	66.66%	2 Missing ⚠️
crates/polars-parquet/src/arrow/write/sink.rs	0.00%	2 Missing ⚠️
crates/polars-arrow/src/io/ipc/write/file_async.rs	0.00%	1 Missing ⚠️
...ates/polars-arrow/src/io/ipc/write/stream_async.rs	0.00%	1 Missing ⚠️
... and 4 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #18564      +/-   ##
==========================================
- Coverage   79.82%   79.82%   -0.01%     
==========================================
  Files        1502     1501       -1     
  Lines      201933   201949      +16     
  Branches     2868     2868              
==========================================
+ Hits       161201   161205       +4     
- Misses      40186    40198      +12     
  Partials      546      546              

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[ritchie46]

Super happy with this one!