fix(package): correct path for demotools export in package.json

package.json

@@ -5,7 +5,7 @@
   "description": "A set of web component tools for creating element catalogues, enabling the structured development and documentation of custom elements and pages.",
   "exports": {
     ".": "./dist_ts_web/index.js",
-    "./demotools": "./dist_ts_demotools"
+    "./demotools": "./dist_ts_demotools/index.js"
   },
   "type": "module",
   "scripts": {