refactor(rust): Don't enable ir_serde together with serde

[JakubValtar]

This PR updates the feature flags so that we can enable ir_serde only on the cloud server, which should reduce the binary size.

[codecov]

Codecov Report

Attention: Patch coverage is 81.57895% with 7 lines in your changes missing coverage. Please review.

Project coverage is 80.33%. Comparing base (4514037) to head (45b2104).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/polars-plan/src/dsl/options/mod.rs	58.82%	7 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #22969   +/-   ##
=======================================
  Coverage   80.32%   80.33%           
=======================================
  Files        1682     1682           
  Lines      223159   223126   -33     
  Branches     2804     2804           
=======================================
- Hits       179262   179241   -21     
+ Misses      43229    43216   -13     
- Partials      668      669    +1     

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