_ensure_uv_for_termux only checked resolve_uv() (the managed
$HERMES_HOME/bin/uv) before falling back to pip, so a uv installed via
`pkg install uv` lives on PATH but is invisible to the helper. Combined
with the cherry-picked wheel-only fallback, a Termux user with no managed
uv still hit `pip install uv`, which has no Android wheel and tried to
source-build the Rust crate, OOM-killing low-memory devices.
Probe shutil.which("uv") right after the Termux guard and reuse it before
pip. Add a regression test that keeps resolve_uv() returning None while a
uv exists on PATH and asserts pip is never invoked.
pefontana
667a9f5139