Add fit_tracking_metrics option to configure_generation_strategy

[saitcakmak]

Summary

Implements the feature requested in #4688: a fit_tracking_metrics option on the high-level Client.configure_generation_strategy API, so users can disable modeling of tracking metrics without manually editing the generation strategy.

client.configure_generation_strategy(fit_tracking_metrics=False)

When False, only metrics in the optimization config (objectives and outcome constraints) are modeled. Tracking metrics are still recorded but not modeled by the BoTorch model — useful when many tracking metrics are kept only for book-keeping.

Changes

• ax/api/client.py — added fit_tracking_metrics: bool = True to configure_generation_strategy and _choose_generation_strategy, threading it into the dispatch struct. Docstrings flag that when False, model-dependent analyses (cross-validation, sensitivity analysis, etc.) will not be produced for tracking metrics, that it requires an optimization config, and that it has no effect for random_search.
• ax/api/utils/structs.py — added the fit_tracking_metrics field to GenerationStrategyDispatchStruct.
• ax/api/utils/generation_strategy_dispatch.py — _get_mbm_node injects fit_tracking_metrics into the MBM node's generator_kwargs; only the MBM node receives it (Sobol/random-search nodes don't model outcomes).
• Tests — added test_gs_fit_tracking_metrics (dispatch) and test_configure_generation_strategy_with_fit_tracking_metrics (client); updated existing tests that assert the full MBM generator_kwargs dict.

Implementation note

fit_tracking_metrics is a TorchAdapter.__init__ kwarg. The registry's kwarg-splitter (ax/adapter/registry.py) automatically routes any key matching an adapter constructor param into the adapter, so adding it to the node's generator_kwargs is sufficient — no changes to registry.py, torch.py, or base.py.

Test plan

• Dispatch tests: 13 passed. Client tests pass. flake8 + ufmt clean.
• End-to-end verified with a genuine tracking metric m2: fit_tracking_metrics=True → modeled outcomes ['m1', 'm2']; False → ['m1'] (tracking metric excluded from modeling).

Closes #4688

[meta-codesync]

@saitcakmak has imported this pull request. If you are a Meta employee, you can view this in D109735998.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.56%. Comparing base (025d7e5) to head (b857fff).

Additional details and impacted files

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##             main    #5238   +/-   ##
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  Coverage   96.56%   96.56%           
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  Files         619      619           
  Lines       70273    70296   +23     
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+ Hits        67861    67884   +23     
  Misses       2412     2412           

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