Fallback to gesvd in invert_subspace on failure

[larsevj]

No description provided.

[Copilot]

Pull request overview

Adds a robustness improvement to the ESMDA subspace inversion routine by retrying SVD with a more stable LAPACK driver when the default driver fails to converge, along with a regression test to ensure the fallback path behaves as intended.

Changes:

• Add gesvd fallback and warning in invert_subspace when sp.linalg.svd raises LinAlgError (non-convergence).
• Add a unit test that monkeypatches scipy.linalg.svd to force gesdd failure and verify fallback + warning + identical numerical result.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
src/iterative_ensemble_smoother/esmda_inversion.py	Wraps SVD in try/except to warn and retry with lapack_driver="gesvd" on failure.
tests/test_esmda_inversion.py	Adds a focused test to ensure the gesdd→gesvd fallback is exercised and produces the same result.

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[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.