Initial commit: Phase 1 scaffolding complete

- Root package.json with concurrently for dev server
- Client: Vite + React 18 with design tokens and proxy config
- Server: Express with CORS, multer (20MB), Sharp resize
- Upload endpoint with preview generation
- Dockerfile (multi-stage) and docker-compose.yml
- Canvas deferred to Phase 8 (export functionality)

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

.gitignore

@@ -0,0 +1,33 @@
+# Dependencies
+node_modules/
+*/node_modules/
+
+# Logs
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+
+# Build outputs
+dist/
+*/dist/
+
+# Environment
+.env
+.env.local
+.env.*.local
+
+# OS
+.DS_Store
+Thumbs.db
+
+# IDE
+.idea/
+.vscode/
+*.swp
+*.swo
+
+# Uploads and exports (keep .gitkeep)
+server/uploads/*
+!server/uploads/.gitkeep
+server/exports/*
+!server/exports/.gitkeep