v0.1.8

Fix Claude subprocess environment scrubbing so custom gateway/auth settings are preserved while host session markers are still removed.\n\n- Preserve Claude auth/provider/gateway environment variables such as CLAUDE_CODE_OAUTH_TOKEN, CLAUDE_CODE_USE_BEDROCK, ANTHROPIC_BASE_URL, and ANTHROPIC_AUTH_TOKEN.\n- Continue scrubbing parent Claude session markers that can misclassify child subprocesses.\n- Add regression coverage for the gateway environment case.