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/skills/dashboard/SKILL.md

@@ -0,0 +1,44 @@
+---
+name: security-dashboard
+description: Cross-project security dashboard — machine-wide posture overview with per-project grades
+---
+
+# Security Dashboard
+
+Machine-wide posture overview. Scans all detected projects, aggregates to a single machine grade (weakest link).
+
+## Step 1: Run Aggregator
+
+```bash
+node <plugin-root>/scanners/dashboard-aggregator.mjs [--no-cache]
+```
+
+Uses 24h cache by default. Pass `--no-cache` to force fresh scan.
+
+## Step 2: Format Dashboard
+
+Parse JSON: `meta`, `machine.grade` (weakest link), `projects[]`, `errors[]`.
+
+```
+# Security Dashboard
+
+| Machine Grade | [A-F] (weakest link) |
+| Projects Scanned | N |
+| Cached | Yes/No |
+
+## Per-Project Grades
+
+| Project | Grade | Risk Score | Verdict | Last Scan |
+|---------|-------|------------|---------|-----------|
+[sorted by grade, worst first]
+
+## Errors (if any)
+
+[List projects that failed to scan]
+```
+
+## Step 3: Recommendations
+
+- Grade A/B: "Machine posture is strong."
+- Grade C: "Review projects with grade C or below."
+- Grade D/F: "Significant exposure. Run audit on failing projects."