The pythonRuntimeUsesUV advanced setting now defaults to on for macOS 13 and later
and off for macOS 12 (the last version this app supports, whose bundled runtime
stays in use; the uv interpreters require macOS 13). The default is computed at
settings-load time from the running OS via a static helper, so users can still
override it in Advanced Settings. Already-provisioned scripts are unaffected; the
gate only governs creating, importing, and migrating scripts.