Add folder anatomy (scripts/agent.py + references/api-reference.md) for 648 cybersecurity skills

Complete skill folder anatomy across all cybersecurity skills:
- scripts/agent.py: 80-150 line Python agents using real libraries (impacket,
  boto3, azure-mgmt-*, kubernetes, pefile, yara, scapy, shodan, stix2, etc.)
- references/api-reference.md: real API documentation with method signatures
- LICENSE: MIT license for all skill folders

skills/implementing-application-whitelisting-with-applocker/references/api-reference.md

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+# API Reference: Implementing Application Whitelisting with AppLocker
+
+## PowerShell AppLocker Management
+
+```powershell
+# Export current policy
+Get-AppLockerPolicy -Effective -Xml | Out-File applocker_policy.xml
+
+# Import policy from XML
+Set-AppLockerPolicy -XmlPolicy applocker_policy.xml
+
+# Test if file is allowed
+Test-AppLockerPolicy -XmlPolicy policy.xml -Path "C:\app.exe" -User Everyone
+
+# Get AppLocker event logs
+Get-WinEvent -LogName "Microsoft-Windows-AppLocker/EXE and DLL"
+```
+
+## AppLocker Event IDs
+
+| Event ID | Type | Meaning |
+|----------|------|---------|
+| 8002 | EXE/DLL | Allowed |
+| 8003 | EXE/DLL | Blocked |
+| 8004 | EXE/DLL | Would block (audit) |
+| 8005 | Script | Allowed |
+| 8006 | Script | Blocked |
+| 8007 | Script | Would block (audit) |
+
+## Rule Collections
+
+| Collection | File Types |
+|------------|------------|
+| Executable | .exe, .com |
+| Windows Installer | .msi, .msp, .mst |
+| Script | .ps1, .bat, .cmd, .vbs, .js |
+| DLL | .dll, .ocx |
+| Packaged App | AppX/MSIX |
+
+## GPO Configuration Path
+
+```
+Computer Configuration > Policies > Windows Settings >
+  Security Settings > Application Control Policies > AppLocker
+```
+
+## Default Rule Paths
+
+```
+%PROGRAMFILES%\*     - Allow Everyone
+%WINDIR%\*           - Allow Everyone
+*                    - Allow BUILTIN\Administrators
+```
+
+### References
+
+- AppLocker: https://learn.microsoft.com/en-us/windows/security/application-security/application-control/app-control-for-business/applocker/applocker-overview
+- AppLocker PowerShell: https://learn.microsoft.com/en-us/powershell/module/applocker/