Milestone 0: import zappier billing, Verae middleware, and Zapier research

Compose-ready workspace: packages/zappier (rate card, portal, Stripe),
packages/verae-zapier-middleware (timestamp + NATS), packages/verae-zapier
(CLI app), vendor/zapier-platform, and research/zapier vendor corpus.

Gate 0 structure checks pass. Product code and research are not yet wired.

vendor/zapier-platform/packages/schema/lib/functional-constraints/deepNestedFields.js

@@ -0,0 +1,68 @@
+'use strict';
+
+const _ = require('lodash');
+const jsonschema = require('jsonschema');
+
+const collectErrors = (inputFields, path) => {
+  const errors = [];
+
+  _.each(inputFields, (inputField, index) => {
+    if (inputField.children) {
+      if (inputField.children.length === 0) {
+        errors.push(
+          new jsonschema.ValidationError(
+            'must not be empty.',
+            inputField,
+            '/PlainFieldSchema',
+            `instance.${path}.inputFields[${index}].children`,
+            'empty',
+            'inputFields',
+          ),
+        );
+      } else {
+        const hasDeeplyNestedChildren = _.some(
+          inputField.children,
+          (child) => child.children,
+        );
+
+        if (hasDeeplyNestedChildren) {
+          errors.push(
+            new jsonschema.ValidationError(
+              'must not contain deeply nested child fields. One level max.',
+              inputField,
+              '/PlainFieldSchema',
+              `instance.${path}.inputFields[${index}]`,
+              'deepNesting',
+              'inputFields',
+            ),
+          );
+        }
+      }
+    }
+  });
+
+  return errors;
+};
+
+const validateFieldNesting = (definition) => {
+  let errors = [];
+
+  _.each(['triggers', 'searches', 'creates'], (typeOf) => {
+    if (definition[typeOf]) {
+      _.each(definition[typeOf], (actionDef) => {
+        if (actionDef.operation && actionDef.operation.inputFields) {
+          errors = errors.concat(
+            collectErrors(
+              actionDef.operation.inputFields,
+              `${typeOf}.${actionDef.key}`,
+            ),
+          );
+        }
+      });
+    }
+  });
+
+  return errors;
+};
+
+module.exports = validateFieldNesting;