Run CI on newest stable Python, which the pins now require

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

.github/workflows/pre-commit.yml

@@ -30,7 +30,7 @@ jobs:
 
       - uses: actions/setup-python@v5
         with:
-          python-version: "3.12"
+          python-version: "3.x"
           # See the note in python-tests.yml: caches the pip download cache,
           # keyed on the real meta/ path rather than the root symlink.
           cache: pip

.github/workflows/python-tests.yml

@@ -42,7 +42,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v5
         with:
-          python-version: "3.11"
+          python-version: "3.x"
           # Cache the pip DOWNLOAD cache, keyed on the requirements file, so a
           # run that changes nothing about dependencies reuses the wheels
           # instead of re-fetching ~80 packages from PyPI. Points at

meta/pyproject.toml

@@ -2,7 +2,10 @@
 name = "testsandmisc"
 version = "0.1.0"
 description = "Collection of miscellaneous tests and scripts"
-requires-python = ">=3.10"
+# numpy 2.5.2 -- the pin the freshness gate requires -- declares >=3.12, so
+# 3.10 and 3.11 can no longer even install the test environment. CI proves
+# 3.14; 3.12 is the lowest version the pins allow.
+requires-python = ">=3.12"
 
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