feat: consider making python-version a required input for semantic-release-uv

[ichoosetoaccept]

Problem

The semantic-release-uv.yml workflow defaults python-version to 3.13. This caused a silent failure in codereviewbuddy (which requires >=3.14) — the release job failed with:

error: The requested interpreter resolved to Python 3.13.12, which is incompatible
with the project's Python requirement: `>=3.14` (from `project.requires-python`)

Options

1. Make python-version required — forces callers to explicitly set it, preventing mismatches
2. Keep optional but document prominently — add a warning to the README that the default may not match your project
3. Auto-detect from pyproject.toml — read requires-python and pick the minimum. More complex but zero config.

Context

• codereviewbuddy PR #26 fixed this by passing python-version: "3.14"
• The pypi-publish job example in the README also doesn't mention python-version, so callers may hit the same issue there