A pyarrow/lance worker thread (loaded via lancedb in lifecycle commands) can
outlive CPython finalization in a one-shot CLI subprocess and trip
PyGILState_Release (SIGABRT, exit -6). It's a thread-timing race — flaky —
and it intermittently red-blocked unrelated PRs: it killed the erase step of
test_cli_lifecycle_round_trip_init_increment_meta_erase on PR #320 (which
touches only installer.py), while the same test passed on green master #319.

Route the installed `java-codebase-rag` entry through _console_script_main,
which flushes stdout/stderr and os._exit(rc) instead of returning into the
racy teardown. main() stays return-based so in-process test callers keep
working.

Co-authored-by: Claude <[email protected]>