The package @biomejs/cli-darwin-x64 contains an embedded executable package/biome which is a Mach-O binary for Darwin (macOS). The file extension mismatch (no extension vs macho) raises a minor concern, but the presence of a pre-compiled binary is a legitimate use case for this type of package, especially given the darwin-x64 in the package name suggesting it's a platform-specific binary. Without further evidence of malicious behavior, it's not possible to classify this as malware.