Moves _QueueStore → bot_bottle/queue_store.py (public QueueStore) and
_AuditStore → bot_bottle/audit_store.py (public AuditStore). Removes
the public queue_db_path() function; QueueStore resolves the DB path
via host_db_path() on the host, or via the SUPERVISE_DB_PATH env var
in the sidecar container (internal mechanism, not public API).
Adds queue_store.py and audit_store.py to Dockerfile.sidecars so the
sidecar bundle picks them up. Updates __all__ in supervise.py.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>