chore: add Vitest scaffolding and sync package.json to v2.2.3

package.json

@@ -1,6 +1,6 @@
 {
   "name": "kicad-mcp",
-  "version": "2.1.0-alpha",
+  "version": "2.2.3",
   "description": "AI-assisted PCB design with KiCAD via Model Context Protocol",
   "type": "module",
   "main": "dist/index.js",
@@ -12,7 +12,8 @@
     "clean": "rm -rf dist",
     "rebuild": "npm run clean && npm run build",
     "test": "npm run test:ts && npm run test:py",
-    "test:ts": "echo 'TypeScript tests not yet configured'",
+    "test:ts": "vitest run",
+    "test:ts:watch": "vitest",
     "test:py": "pytest tests/ -v",
     "test:coverage": "pytest tests/ --cov=python --cov-report=html --cov-report=term",
     "lint": "npm run lint:ts && npm run lint:py",
@@ -48,6 +49,7 @@
     "nodemon": "^3.0.1",
     "prettier": "^3.8.1",
     "typescript": "^5.9.3",
-    "typescript-eslint": "^8.57.2"
+    "typescript-eslint": "^8.57.2",
+    "vitest": "^2.1.9"
   }
 }