turn on no-namespace rule

Author: danielpza

eslint.config.mjs

@@ -13,7 +13,7 @@ export default [
       "@typescript-eslint/ban-ts-comment": "warn",
       "@typescript-eslint/no-empty-object-type": "warn",
       "@typescript-eslint/no-explicit-any": "off",
-      "@typescript-eslint/no-namespace": "warn",
+      "@typescript-eslint/no-namespace": ["error", { allowDeclarations: true }],
       "@typescript-eslint/no-require-imports": "off",
       "@typescript-eslint/no-unsafe-function-type": "warn",
       "@typescript-eslint/no-unused-vars": "warn",