refactor(rust): Move physical expressions to new crate

[ritchie46]

This will make it easier to share them between different engines that don't depend on polars-lazy.

[codecov]

Codecov Report

Attention: Patch coverage is 72.26891% with 33 lines in your changes are missing coverage. Please review.

Project coverage is 81.33%. Comparing base (e214e93) to head (37855e7).
Report is 6 commits behind head on main.

Files	Patch %	Lines
crates/polars-core/src/datatypes/any_value.rs	0.00%	14 Missing ⚠️
py-polars/src/lazyframe/visitor/expr_nodes.rs	0.00%	12 Missing ⚠️
...rs-lazy/src/physical_plan/streaming/convert_alp.rs	0.00%	4 Missing ⚠️
crates/polars-pipe/src/pipeline/convert.rs	33.33%	2 Missing ⚠️
crates/polars-expr/src/state/execution_state.rs	97.05%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #16306      +/-   ##
==========================================
+ Coverage   80.76%   81.33%   +0.56%     
==========================================
  Files        1393     1403      +10     
  Lines      179415   183295    +3880     
  Branches     2921     2924       +3     
==========================================
+ Hits       144910   149078    +4168     
+ Misses      34002    33714     -288     
  Partials      503      503              

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