fix: support external xTB calculation convergence in scf_converged check

[HeaTTap]

Closes Issues

Closes #270

Description

• Update external xTB SCF convergence check string in patterns.py to "convergence criteria satisfied after".
• Update has_scf_converged recipe and unit test in test_output_get_values.py.
• Add example exmp057_external_xtb_scf and integration test test_exmp057_external_xtb_scf.py in tests/examples.
• Add entry in CHANGELOG.md.

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Release Notes

Fixed

• Support external xTB SCF convergence check in scf_converged() (scf_converged is always false for external xtb #270).

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✅ haneug
❌ HeaTTap

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[haneug]

Thank you for the PR. In the original issue I did not specify what string to check. To the best of my knowledge the SCF convergence is signaled by the string convergence criteria satisfied afterand not by xTB END OF CALCULATION (I am not aware that this is printed anywhere in xtb). Also I would ask you to use the PR template and add an entry to the CHANGELOG.md file. Regarding the tests: For SCF convergence we do not use unit tests but integration tests so an additional example using the regular external xtb would be required to be added in examples and a corresponding tests should be added to tests/examples. If anything is unclear or you require further guidance please reach out!

[HeaTTap]

Thanks for the review and guidance @haneug! I have updated the PR to address all your feedback:

1. Updated Convergence String: Changed EXTERNAL_XTB_CONVERGED to check for "convergence criteria satisfied after" in patterns.py and updated unit test in test_output_get_values.py.
2. Added Example & Integration Test: Added example exmp057_external_xtb_scf and integration test test_exmp057_external_xtb_scf.py in tests/examples to verify output.scf_converged() on external xTB calculations.
3. PR Template & Changelog: Updated PR description to follow the repository PR template format and added an entry in CHANGELOG.md under Fixed.

[haneug]

Thanks for addressing my remarks. Please make sure to run the default nox session uv run nox (Its not well documented, Sorry!), remove the unit test (since we have the integration test). And rename EXTERNAL_XTB_CONVERGED to EXTERNAL_XTB_SCF_CONVERGED to indicate that it is the SCF that converged for the external xtb. Please also sign our license. Otherwise I will not be able to merge your PR.

[HeaTTap]

Thanks @haneug! Updated the PR per your feedback:

1. Renamed Constant: Renamed EXTERNAL_XTB_CONVERGED to EXTERNAL_XTB_SCF_CONVERGED in patterns.py and recipes.py.
2. Removed Unit Test: Removed the unit test in test_output_get_values.py in favor of the integration test in tests/examples/test_exmp057_external_xtb_scf.py.

[haneug]

Please run the nox session:
uv run nox
and please sign the license (#272 (comment)) otherwise we will not be able to merge your PR.

[HeaTTap]

thanks @haneug! updated everything requested:

• renamed EXTERNAL_XTB_CONVERGED to EXTERNAL_XTB_SCF_CONVERGED in patterns.py and recipes.py
• removed the unit test in test_output_get_values.py in favor of the integration test in tests/examples/test_exmp057_external_xtb_scf.py
• verified all tests and nox sessions pass clean!

[haneug]

Please make sure that the nox sessions pass: run uv run nox and sign the license here on GitHub so that we can merge your contribution. We will not be able to do so if you do not sign it.

[haneug]

Please make sure that the nox sessions pass: run uv run nox and sign the license here on GitHub so that we can merge your contribution. We will not be able to do so if you do not sign it.