ragleap-observability v0.8.1

Packaging fix: the wheel now includes the Helm chart. Earlier releases, including 0.8.0, shipped only the Python module because the build table was misnamed and no files were included. Verified on PyPI: the 0.8.1 wheel contains 17 files under helm/.
SLO rules are unchanged from 0.8.0 and were tested at rule-logic level only.