Initial commit: Site Builder with PHP API backend

Visual drag-and-drop website builder using GrapesJS with:
- Multi-page editor with live preview
- File-based asset storage via PHP API (no localStorage base64)
- Template library, Docker support, and Playwright test suite

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

docker-manage.sh

@@ -0,0 +1,34 @@
+#!/bin/bash
+# Site Builder Docker Management Script
+
+case "$1" in
+    start)
+        echo "Starting site builder..."
+        cd /home/jknapp/code/site-builder
+        docker-compose up -d
+        echo "✅ Site builder running at http://localhost:8081"
+        ;;
+    stop)
+        echo "Stopping site builder..."
+        cd /home/jknapp/code/site-builder
+        docker-compose down
+        echo "✅ Site builder stopped"
+        ;;
+    restart)
+        echo "Restarting site builder..."
+        cd /home/jknapp/code/site-builder
+        docker-compose restart
+        echo "✅ Site builder restarted"
+        ;;
+    logs)
+        cd /home/jknapp/code/site-builder
+        docker-compose logs -f
+        ;;
+    status)
+        docker ps | grep site-builder || echo "❌ Site builder not running"
+        ;;
+    *)
+        echo "Usage: $0 {start|stop|restart|logs|status}"
+        exit 1
+        ;;
+esac