Review MolSysSuite Python ecosystem policy in PyUnitWizard

[LMMV]

What

Complete PyUnitWizard's review of the MolSysSuite Python ecosystem policy. Developer-tool adoption is verified, and published ArgDigest 0.13.0 integration is exercised in hosted CI. The support-library review remains partial because native public argument checks still need an applicability decision.

How

• Retain the published pytest-receptor 1.1.0 pin and ci profile in hosted tests.
• Retain the ArgDigest 0.13.0 test-environment pin and import checks added in 00d4707. Routine CI 36335377594, policy 36335377971, release gates 36335382518, and eight-cell matrix 36335382533 passed on that source commit.
• Audit public checks such as configure.load_library() and configure.set_standard_units(). Decide which ordinary argument constraints should use ArgDigest and which physical or integrity checks must remain local. If proposing a required reverse dependency, test dependency closure and clean import orders; otherwise document a bounded provider exception under the suite policy.

Why

Successful optional adapter tests establish interoperability but do not settle PyUnitWizard's own public validation boundary. The inventory must remain partial until that decision has implementation or a justified exception.

Acceptance

• Every applicable support-library boundary has implementation and test evidence, or a bounded exception with its reassessment condition.
• The MolSysSuite inventory records the final decision and exact evidence.

Record: devguide/pending_proposals/2026-09-25-python-ecosystem-policy-review.md.

[LMMV]

The inherited Python ecosystem review is recorded in source commit c8cd856 and the developer-guide record. The follow-up evidence commit is f7785fd.

Developer tools: adopted. The three pytest environments pin published pytest-receptor 1.1.0; routine CI, the eight-cell matrix, and release gates use --receptor=ci without changing their gates. Local --receptor=llm passed 596 tests with 8 skips. The exact source commit passed routine CI (622 passed, 5 skipped), MolSysSuite policy, eight-cell matrix, and release gates. GH Run Receptor inspected all four; the native CI log confirms pytest-receptor 1.1.0 py_1 from uibcdf and the ci profile. Ruff, the report index, and the MolSysSuite repository checker pass.

Support libraries: partial. SMonitor diagnostics, DepDigest optional-backend handling, and PyUnitWizard's physical-quantity boundary have tests. Six local ecosystem tests exercise ArgDigest's optional PyUnitWizard adapter and collective error path, but ArgDigest is absent from hosted test environments, so published integration across the claimed Python minors remains unproven. This issue also retains the applicability decision for native public argument checks and the potential dependency cycle. It remains open for that work.

MolSysSuite records these separate states in 371459d.

[dprada]

Progress at source 00d4707; report updated at 4ffe2f1. Published ArgDigest 0.13.0 is pinned in the development, test, and release-gate environments. Exact-commit routine CI 36335377594, policy 36335377971, release gates 36335382518, and 8-cell Linux/macOS matrix 36335382533 passed. Native logs confirm ArgDigest 0.13.0 imports on Python 3.11–3.14; each matrix cell passed 634 tests with three unrelated skips. The optional adapter evidence gap is resolved. This issue remains open and support-library adoption remains partial while we decide which native public argument checks (for example configure.load_library and configure.set_standard_units) should use ArgDigest and whether the provider boundary warrants a bounded exception. A required reverse dependency would need separate dependency and import-order analysis. Record: devguide/pending_proposals/2026-09-25-python-ecosystem-policy-review.md.