feat: add official skills-ref validation script

Added validate-skills-official.sh that uses the official skills-ref
library from https://github.com/agentskills/agentskills for validation.

This replaces the custom bash validation with the canonical implementation
used by the Agent Skills project. All 25 skills pass validation.

Usage: ./validate-skills-official.sh

https://claude.ai/code/session_01DboBqyncsUPg5Z5qpLJx4x

validate-skills-official.sh

@@ -0,0 +1,85 @@
+#!/bin/bash
+
+# Validation script using official skills-ref library
+# https://github.com/agentskills/agentskills/tree/main/skills-ref
+
+SKILLS_DIR="skills"
+SKILLS_REF_DIR="/tmp/agentskills/skills-ref"
+
+echo "🔍 Validating Skills Using Official skills-ref Library"
+echo "========================================================"
+echo "Reference: https://github.com/agentskills/agentskills"
+echo ""
+
+# Check if skills-ref is already installed
+if [ ! -d "$SKILLS_REF_DIR/.venv" ]; then
+    echo "📦 Installing skills-ref library..."
+    echo ""
+
+    if [ ! -d "$SKILLS_REF_DIR" ]; then
+        cd /tmp
+        git clone https://github.com/agentskills/agentskills.git
+    fi
+
+    cd "$SKILLS_REF_DIR"
+
+    if command -v uv &> /dev/null; then
+        echo "Using uv to install..."
+        uv sync
+    else
+        echo "Using pip to install..."
+        python3 -m venv .venv
+        source .venv/bin/activate
+        pip install -e .
+    fi
+    echo ""
+fi
+
+# Activate the virtual environment
+source "$SKILLS_REF_DIR/.venv/bin/activate"
+
+# Return to the original directory
+cd "$(dirname "$0")"
+
+# Track results
+PASSED=0
+FAILED=0
+FAILED_SKILLS=()
+
+echo "Running validation..."
+echo ""
+
+# Validate each skill
+for skill_dir in "$SKILLS_DIR"/*/; do
+    skill_name=$(basename "$skill_dir")
+    printf "  %-30s" "$skill_name"
+
+    output=$(skills-ref validate "$skill_dir" 2>&1)
+    if echo "$output" | grep -q "Valid skill"; then
+        echo "✓"
+        ((PASSED++))
+    else
+        echo "✗"
+        ((FAILED++))
+        FAILED_SKILLS+=("$skill_name")
+        echo "$output" | sed 's/^/    /'
+    fi
+done
+
+echo ""
+echo "========================================================"
+echo "Summary:"
+echo "  ✓ Passed: $PASSED"
+echo "  ✗ Failed: $FAILED"
+echo ""
+
+if [ $FAILED -eq 0 ]; then
+    echo "✅ All skills are valid!"
+    exit 0
+else
+    echo "❌ Failed skills:"
+    for skill in "${FAILED_SKILLS[@]}"; do
+        echo "  - $skill"
+    done
+    exit 1
+fi