Propagate stable code identifier pickling and preserve pickler config

[kristynsmith]

Previously, Pipeline.to_runner_api did not forward the runner's enable_stable_code_identifier_pickling setting onto PipelineContext, preventing downstream transforms from using stable code object identifiers during Runner API serialization. Additionally, enabling enable_stable_code_identifier_pickling in cloudpickle_pickler replaced the active config with a static STABLE_CODE_IDENTIFIER_CONFIG instance initialized at import time, discarding runtime overrides made to DEFAULT_CONFIG (such as custom id_generator and pickle_main_by_ref settings).

Copy enable_stable_code_identifier_pickling from the runner onto PipelineContext in Pipeline.to_runner_api, and use dataclasses.replace in cloudpickle_pickler._dumps so get_code_object_params is updated without overwriting other fields on the active CloudPickleConfig.

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[github-actions]

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 79.56%. Comparing base (c275c97) to head (88ae832).
⚠️ Report is 137 commits behind head on master.

Additional details and impacted files

@@              Coverage Diff              @@
##             master   #40453       +/-   ##
=============================================
+ Coverage     56.20%   79.56%   +23.35%     
=============================================
  Files          1123      487      -636     
  Lines        178213    82226    -95987     
  Branches       1489        0     -1489     
=============================================
- Hits         100168    65421    -34747     
+ Misses        75524    16805    -58719     
+ Partials       2521        0     -2521     

Flag	Coverage Δ
go	?
java	?
python	79.56% <100.00%> (-0.12%)	⬇️

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[github-actions]

Assigning reviewers:

R: @tvalentyn for label python.

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[tvalentyn]

Reached out to @kristynsmith offline

[tvalentyn]

waiting on author