Generic harness quickstart

1. Preview: openclaw-mem install --harness generic --root . --dry-run --json.
2. Install the portable skill: openclaw-mem install --harness generic --root . --verify --json.
3. Configure the harness's stdio MCP command as openclaw-mem-mcp.
4. Diagnose later with openclaw-mem doctor --harness generic --root . --json.

Override the portable skill root with --skills-dir.