chore: require Python 3.8, since ipyvue 3.1.0 does not import on 3.7

[maartenbreddels]

ipyvue now declares that it needs Python 3.8 or newer, because ipyvue 3.1.0 already does not import on Python 3.7.

Problem

ipyvue 3.1.0 uses an assignment expression (:=) in ipyvue/esm.py, line 91. Python 3.7 cannot parse it.
The 3.1.0 package declares no minimum Python version, so pip on Python 3.7 still installs it.
Then import ipyvue fails with a SyntaxError, and so does import ipyvuetify, which depends on ipyvue>=3.0.0.
ipyvuetify's CI showed it: its test (3.7) job fails with ipyvue 3.1.0.
Python 3.7 has been end of life since June 2023, and CI here already tests only 3.8 and newer.

Change

• setup.py sets python_requires=">=3.8".

Validation

• Claude checked the sources of 3.1.0 and 1.13.0 against the Python 3.7 grammar (Python 3.12's ast.parse with feature_version=(3, 7)). 3.1.0 fails at ipyvue/esm.py:91. 1.13.0 parses.
• ipyvuetify's CI against ipyvue 3.1.0 fails only on Python 3.7, with the same SyntaxError.

Gaps

• The next release carries the new metadata. 3.1.0 itself has none, so pip on Python 3.7 still picks 3.1.0. Yanking 3.1.0 on PyPI after the next release keeps Python 3.7 users on 3.0.0, which works there.
• The 1.x line does not change.
• ipyvuetify gets the same change in chore: require Python 3.8 on 3.x, since ipyvue 3.1.0 does not import on 3.7 ipyvuetify#348.

Align results

• Drop Python 3.7: Maarten, 2026-10-05: "lets drop 3.7 right? for 3.x".

Crossreview results

Round 1, by astra and gpt-6.1-sol, on both companion PRs together. Neither found a defect. Both noted older things this PR does not change: some ipyvue UI-test skip messages still name old Python versions, and the setuptools minimum in ipyvuetify is out of date.

🤖 Generated with Claude Code