refactor(core): add phpstat.neon config file

phpstan.neon

@@ -1,6 +1,9 @@
 parameters:
-  level: 6
-  bootstrapFiles:
-    - index.php
+  level: max
   paths:
     - src
+  ignoreErrors:
+    - '/Constant PATH not found./'
+    - '/Constant ROOT_DIR not found./'
+    - '/Variable \$api_errors might not be defined./'
+    - '/Variable \$registry might not be defined./'