[jon-devlapaz]

Controlled Tinkery workflow replay in this personal fork. This is a trial result for operator review, not an upstream contribution or a claim that this feature is new. It replays the public request from python-humanize#214; a separate upstream implementation was already identified in python-humanize#316.

natural_list accepts conjunction: str = "and", preserving existing defaults and allowing strings such as "or" and "and also". The change is limited to the function, its docstring and focused tests. It performs no translation.

Validation at c7011211debdde8fa95f0a698c5fed616cb1ece5:

• Full local tox suite: 760 passed, 132 localization skips; all 15 benchmarks included. Isolated Python 3.14.7 / pytest 9.1.1 (9.2.0 exposed an existing benchmark-plugin incompatibility before the feature).
• Focused tests and doctest: 29 passed. All 14 added cases failed on the original function.
• Restoring hard-coded and while retaining the new parameter makes 11 custom cases fail; all 14 original default cases still pass. Restoring the implementation passes again.
• SDLC verification is current, with the imported seed command proven. Independent review found no blocking findings or nits for this exact candidate. No human acceptance is recorded. The new fork reports no remote CI checks.

Trial trace: run be4610f1-1e0b-4078-b938-52cd8e68fd36; seed SHA-256 53f241a3821054a96bb04847354e37e72a8b87fa9408307ec721c5ff87bba19c; baseline 6b817b963dbb091b9ad20a746cb6a26653a93b95. The seed was explicitly confirmed by an agent acting under operator authorization.

The trial caught a faulty seed proposal: its broad pytest -k natural_list command passed before the feature existed. We preserved that finding, then added real regressions and the production-only reversion check during implementation. Passing the final command does not erase the earlier failure. The related Tinkery correction is jon-devlapaz/tinkery#470.

Keep this PR as a draft for the operator's judgment. Nothing is submitted to the upstream repository.