feat: add shannon pentesting skill and AGPL-3.0 license

Copy the shannon skill from unicodeveloper/shannon into the Agent Skills
repo. Add proper full AGPL-3.0 license text to respect upstream licensing.
Update CLAUDE.md to document the new skill.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

shannon/scripts/setup-shannon.sh

@@ -0,0 +1,60 @@
+#!/usr/bin/env bash
+# setup-shannon.sh - Install or update Shannon pentester
+# Usage: bash scripts/setup-shannon.sh [SHANNON_HOME]
+set -euo pipefail
+
+SHANNON_HOME="${1:-${SHANNON_HOME:-$HOME/shannon}}"
+
+echo "🔐 Shannon Setup"
+echo "━━━━━━━━━━━━━━━━"
+
+# Check Docker
+if ! command -v docker &>/dev/null; then
+  echo "❌ Docker is required but not installed."
+  echo "   Install: https://docker.com/products/docker-desktop"
+  exit 1
+fi
+echo "✅ Docker: $(docker --version 2>/dev/null | head -1)"
+
+# Check git
+if ! command -v git &>/dev/null; then
+  echo "❌ Git is required but not installed."
+  exit 1
+fi
+echo "✅ Git: $(git --version)"
+
+# Clone or update Shannon
+if [ -d "$SHANNON_HOME" ] && [ -f "$SHANNON_HOME/shannon" ]; then
+  echo "✅ Shannon found at $SHANNON_HOME"
+  echo "   Updating..."
+  cd "$SHANNON_HOME" && git pull --ff-only 2>/dev/null || echo "   (already up to date or can't fast-forward)"
+else
+  echo "📥 Cloning Shannon to $SHANNON_HOME..."
+  git clone https://github.com/KeygraphHQ/shannon.git "$SHANNON_HOME"
+  echo "✅ Shannon cloned successfully"
+fi
+
+# Check API credentials
+echo ""
+echo "API Credentials:"
+if [ -n "${ANTHROPIC_API_KEY:-}" ]; then
+  echo "✅ ANTHROPIC_API_KEY is set"
+elif [ -n "${CLAUDE_CODE_OAUTH_TOKEN:-}" ]; then
+  echo "✅ CLAUDE_CODE_OAUTH_TOKEN is set"
+elif [ "${CLAUDE_CODE_USE_BEDROCK:-}" = "1" ]; then
+  echo "✅ AWS Bedrock mode enabled"
+elif [ "${CLAUDE_CODE_USE_VERTEX:-}" = "1" ]; then
+  echo "✅ Google Vertex AI mode enabled"
+else
+  echo "⚠️  No AI credentials detected. Set one of:"
+  echo "   export ANTHROPIC_API_KEY=sk-ant-..."
+  echo "   export CLAUDE_CODE_OAUTH_TOKEN=..."
+  echo "   export CLAUDE_CODE_USE_BEDROCK=1"
+  echo "   export CLAUDE_CODE_USE_VERTEX=1"
+fi
+
+echo ""
+echo "Recommended: export CLAUDE_CODE_MAX_OUTPUT_TOKENS=64000"
+echo ""
+echo "Shannon is ready at: $SHANNON_HOME"
+echo "Run a pentest:  cd $SHANNON_HOME && ./shannon start URL=http://localhost:3000 REPO=myapp"

shannon/scripts/sync.sh

@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+# sync.sh - Deploy shannon skill to all host locations
+# Usage: bash scripts/sync.sh  (run from repo root)
+set -euo pipefail
+
+SRC="$(cd "$(dirname "$0")/.." && pwd)"
+echo "Source: $SRC"
+
+TARGETS=(
+  "$HOME/.claude/skills/shannon"
+  "$HOME/.agents/skills/shannon"
+  "$HOME/.codex/skills/shannon"
+)
+
+for t in "${TARGETS[@]}"; do
+  echo ""
+  echo "--- Syncing to $t ---"
+  mkdir -p "$t/scripts"
+
+  cp "$SRC/SKILL.md" "$t/"
+
+  # Helper scripts
+  if ls "$SRC/scripts/"*.sh &>/dev/null; then
+    rsync -a "$SRC/scripts/"*.sh "$t/scripts/"
+  fi
+
+  echo "  Deployed to $t"
+done
+
+echo ""
+echo "Sync complete."