streamSimple routes to streamViaAcp ONLY when FUSION_CLAUDE_ACP=1 AND a bridge path is provided; otherwise stays on the -p streamViaCli path. Covers the three cases (off / flag-without-path / flag+path) and asserts the bridge path + env are forwarded. 333/333 pi-claude-cli tests green. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>