fix composer deps

Author: t-heuser

composer.json

@@ -12,10 +12,13 @@
   },
   "require": {
     "guzzlehttp/psr7": "^2.0",
-    "php": "^8.1",
-    "neos/neos": "^9.0"
+    "php": "^8.1"
+  },
+  "conflict": {
+    "neos/neos": "<9.0"
   },
   "require-dev": {
+    "neos/neos": "^9.0",
     "neos/contentrepositoryregistry-doctrinedbalclient": "*",
     "phpstan/phpstan": "^2.1",
     "phpstan/phpstan-phpunit": "^2.0",