fix(demo): broken due to vitest/esbuild upgrade

Author: urish

tsconfig.json

@@ -9,7 +9,8 @@
     "declaration": true,
     "esModuleInterop": true /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */,
     "skipLibCheck": true /* Skip type checking of declaration files. */,
-    "forceConsistentCasingInFileNames": true /* Disallow inconsistently-cased references to the same file. */
+    "forceConsistentCasingInFileNames": true /* Disallow inconsistently-cased references to the same file. */,
+    "useDefineForClassFields": false
   },
   "include": ["src/**/*.ts"],
   "exclude": ["src/**/*.spec.ts"]