feat(llm-security-copilot): port llm-security v5.1.0 to GitHub Copilot CLI

Full port of llm-security plugin for internal use on Windows with GitHub
Copilot CLI. Protocol translation layer (copilot-hook-runner.mjs)
normalizes Copilot camelCase I/O to Claude Code snake_case format — all
original hook scripts run unmodified.

- 8 hooks with protocol translation (stdin/stdout/exit code)
- 18 SKILL.md skills (Agent Skills Open Standard)
- 6 .agent.md agent definitions
- 20 scanners + 14 scanner lib modules (unchanged)
- 14 knowledge files (unchanged)
- 39 test files including copilot-port-verify.mjs (17 tests)
- Windows-ready: node:path, os.tmpdir(), process.execPath, no bash

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

plugins/llm-security-copilot/hooks/scripts/lib/windows-paths.mjs

@@ -0,0 +1,25 @@
+// windows-paths.mjs — Additional path patterns for Windows environments.
+// Loaded by copilot-hook-runner.mjs when running on Windows.
+//
+// The original pre-write-pathguard.mjs has Unix-specific SYSTEM_PATTERNS
+// that won't match on Windows. This module exports additional patterns
+// for Windows system directories.
+
+export const WINDOWS_SYSTEM_PATTERNS = [
+  /^[A-Z]:\\Windows\\/i,
+  /^[A-Z]:\\Program Files/i,
+  /^[A-Z]:\\Program Files \(x86\)/i,
+  /^[A-Z]:\\ProgramData\\/i,
+  /^[A-Z]:\\System Volume Information/i,
+];
+
+export const WINDOWS_CREDENTIAL_PATHS = [
+  /[\\/]\.docker[\\/]config\.json$/i,
+  /[\\/]\.kube[\\/]config$/i,
+  /[\\/]\.azure[\\/]/i,
+  /[\\/]\.aws[\\/]/i,
+  /[\\/]\.ssh[\\/]/i,
+  /[\\/]\.gnupg[\\/]/i,
+  /[\\/]AppData[\\/]Local[\\/]Google[\\/]Chrome[\\/]User Data/i,
+  /[\\/]AppData[\\/]Local[\\/]Microsoft[\\/]Edge[\\/]User Data/i,
+];