Add HA lifecycle tests and CI

scripts/check.sh

@@ -0,0 +1,11 @@
+#!/bin/sh
+# Run with Python 3.13 and requirements-test.txt installed.
+set -eu
+# A transitive HA test dependency otherwise fetches metadata on import.
+export LITELLM_LOCAL_MODEL_COST_MAP=True
+python -m pip check
+python -m unittest discover -s tests -v
+python -m pytest tests/ha -q
+python -m compileall -q custom_components/heating_mpc
+python scripts/validate_package.py
+git diff --check