Security: Detect PowerShell/Ruby/Perl command execution

## Bypass Description

Alternative interpreters can execute install commands:

```bash
pwsh -c "npm install malicious"
ruby -e "system('npm install evil')"
perl -e "exec('pip install malware')"
```

## Difficulty: Medium

Need to add detection for pwsh, ruby -e, perl -e patterns.

## Priority: Medium

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Found in security audit 2024-01-06