chore: enable missing scopes lint rule as error

Author: rpocklin

validator/xero-spectral.yaml

@@ -159,3 +159,4 @@ rules:
   owasp:api4:2023-string-restricted: off  # Disable string restricted rule to address warnings
   path-params: off  # Disable path parameter validation to address mapping key issues
   owasp:api8:2023-define-cors-origin: off  # Disable CORS origin header requirement
+  oas3-operation-security-defined: error # Ensure all scopes are listed in schema